-
Notifications
You must be signed in to change notification settings - Fork 23
/
Copy pathHigh_Availability_Guide.html
5768 lines (5714 loc) · 296 KB
/
High_Availability_Guide.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="generator" content="Asciidoctor 2.0.17">
<meta name="author" content="WildFly clustering team">
<title>High Availability Guide</title>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700">
<style>
/*! Asciidoctor default stylesheet | MIT License | https://asciidoctor.org */
/* Uncomment the following line when using as a custom stylesheet */
/* @import "https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700"; */
html{font-family:sans-serif;-webkit-text-size-adjust:100%}
a{background:none}
a:focus{outline:thin dotted}
a:active,a:hover{outline:0}
h1{font-size:2em;margin:.67em 0}
b,strong{font-weight:bold}
abbr{font-size:.9em}
abbr[title]{cursor:help;border-bottom:1px dotted #dddddf;text-decoration:none}
dfn{font-style:italic}
hr{height:0}
mark{background:#ff0;color:#000}
code,kbd,pre,samp{font-family:monospace;font-size:1em}
pre{white-space:pre-wrap}
q{quotes:"\201C" "\201D" "\2018" "\2019"}
small{font-size:80%}
sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}
sup{top:-.5em}
sub{bottom:-.25em}
img{border:0}
svg:not(:root){overflow:hidden}
figure{margin:0}
audio,video{display:inline-block}
audio:not([controls]){display:none;height:0}
fieldset{border:1px solid silver;margin:0 2px;padding:.35em .625em .75em}
legend{border:0;padding:0}
button,input,select,textarea{font-family:inherit;font-size:100%;margin:0}
button,input{line-height:normal}
button,select{text-transform:none}
button,html input[type=button],input[type=reset],input[type=submit]{-webkit-appearance:button;cursor:pointer}
button[disabled],html input[disabled]{cursor:default}
input[type=checkbox],input[type=radio]{padding:0}
button::-moz-focus-inner,input::-moz-focus-inner{border:0;padding:0}
textarea{overflow:auto;vertical-align:top}
table{border-collapse:collapse;border-spacing:0}
*,::before,::after{box-sizing:border-box}
html,body{font-size:100%}
body{background:#fff;color:rgba(0,0,0,.8);padding:0;margin:0;font-family:"Noto Serif","DejaVu Serif",serif;line-height:1;position:relative;cursor:auto;-moz-tab-size:4;-o-tab-size:4;tab-size:4;word-wrap:anywhere;-moz-osx-font-smoothing:grayscale;-webkit-font-smoothing:antialiased}
a:hover{cursor:pointer}
img,object,embed{max-width:100%;height:auto}
object,embed{height:100%}
img{-ms-interpolation-mode:bicubic}
.left{float:left!important}
.right{float:right!important}
.text-left{text-align:left!important}
.text-right{text-align:right!important}
.text-center{text-align:center!important}
.text-justify{text-align:justify!important}
.hide{display:none}
img,object,svg{display:inline-block;vertical-align:middle}
textarea{height:auto;min-height:50px}
select{width:100%}
.subheader,.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{line-height:1.45;color:#7a2518;font-weight:400;margin-top:0;margin-bottom:.25em}
div,dl,dt,dd,ul,ol,li,h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6,pre,form,p,blockquote,th,td{margin:0;padding:0}
a{color:#2156a5;text-decoration:underline;line-height:inherit}
a:hover,a:focus{color:#1d4b8f}
a img{border:0}
p{line-height:1.6;margin-bottom:1.25em;text-rendering:optimizeLegibility}
p aside{font-size:.875em;line-height:1.35;font-style:italic}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{font-family:"Open Sans","DejaVu Sans",sans-serif;font-weight:300;font-style:normal;color:#ba3925;text-rendering:optimizeLegibility;margin-top:1em;margin-bottom:.5em;line-height:1.0125em}
h1 small,h2 small,h3 small,#toctitle small,.sidebarblock>.content>.title small,h4 small,h5 small,h6 small{font-size:60%;color:#e99b8f;line-height:0}
h1{font-size:2.125em}
h2{font-size:1.6875em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.375em}
h4,h5{font-size:1.125em}
h6{font-size:1em}
hr{border:solid #dddddf;border-width:1px 0 0;clear:both;margin:1.25em 0 1.1875em}
em,i{font-style:italic;line-height:inherit}
strong,b{font-weight:bold;line-height:inherit}
small{font-size:60%;line-height:inherit}
code{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;font-weight:400;color:rgba(0,0,0,.9)}
ul,ol,dl{line-height:1.6;margin-bottom:1.25em;list-style-position:outside;font-family:inherit}
ul,ol{margin-left:1.5em}
ul li ul,ul li ol{margin-left:1.25em;margin-bottom:0}
ul.square li ul,ul.circle li ul,ul.disc li ul{list-style:inherit}
ul.square{list-style-type:square}
ul.circle{list-style-type:circle}
ul.disc{list-style-type:disc}
ol li ul,ol li ol{margin-left:1.25em;margin-bottom:0}
dl dt{margin-bottom:.3125em;font-weight:bold}
dl dd{margin-bottom:1.25em}
blockquote{margin:0 0 1.25em;padding:.5625em 1.25em 0 1.1875em;border-left:1px solid #ddd}
blockquote,blockquote p{line-height:1.6;color:rgba(0,0,0,.85)}
@media screen and (min-width:768px){h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2}
h1{font-size:2.75em}
h2{font-size:2.3125em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.6875em}
h4{font-size:1.4375em}}
table{background:#fff;margin-bottom:1.25em;border:1px solid #dedede;word-wrap:normal}
table thead,table tfoot{background:#f7f8f7}
table thead tr th,table thead tr td,table tfoot tr th,table tfoot tr td{padding:.5em .625em .625em;font-size:inherit;color:rgba(0,0,0,.8);text-align:left}
table tr th,table tr td{padding:.5625em .625em;font-size:inherit;color:rgba(0,0,0,.8)}
table tr.even,table tr.alt{background:#f8f8f7}
table thead tr th,table tfoot tr th,table tbody tr td,table tr td,table tfoot tr td{line-height:1.6}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2;word-spacing:-.05em}
h1 strong,h2 strong,h3 strong,#toctitle strong,.sidebarblock>.content>.title strong,h4 strong,h5 strong,h6 strong{font-weight:400}
.center{margin-left:auto;margin-right:auto}
.stretch{width:100%}
.clearfix::before,.clearfix::after,.float-group::before,.float-group::after{content:" ";display:table}
.clearfix::after,.float-group::after{clear:both}
:not(pre).nobreak{word-wrap:normal}
:not(pre).nowrap{white-space:nowrap}
:not(pre).pre-wrap{white-space:pre-wrap}
:not(pre):not([class^=L])>code{font-size:.9375em;font-style:normal!important;letter-spacing:0;padding:.1em .5ex;word-spacing:-.15em;background:#f7f7f8;border-radius:4px;line-height:1.45;text-rendering:optimizeSpeed}
pre{color:rgba(0,0,0,.9);font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;line-height:1.45;text-rendering:optimizeSpeed}
pre code,pre pre{color:inherit;font-size:inherit;line-height:inherit}
pre>code{display:block}
pre.nowrap,pre.nowrap pre{white-space:pre;word-wrap:normal}
em em{font-style:normal}
strong strong{font-weight:400}
.keyseq{color:rgba(51,51,51,.8)}
kbd{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;display:inline-block;color:rgba(0,0,0,.8);font-size:.65em;line-height:1.45;background:#f7f7f7;border:1px solid #ccc;border-radius:3px;box-shadow:0 1px 0 rgba(0,0,0,.2),inset 0 0 0 .1em #fff;margin:0 .15em;padding:.2em .5em;vertical-align:middle;position:relative;top:-.1em;white-space:nowrap}
.keyseq kbd:first-child{margin-left:0}
.keyseq kbd:last-child{margin-right:0}
.menuseq,.menuref{color:#000}
.menuseq b:not(.caret),.menuref{font-weight:inherit}
.menuseq{word-spacing:-.02em}
.menuseq b.caret{font-size:1.25em;line-height:.8}
.menuseq i.caret{font-weight:bold;text-align:center;width:.45em}
b.button::before,b.button::after{position:relative;top:-1px;font-weight:400}
b.button::before{content:"[";padding:0 3px 0 2px}
b.button::after{content:"]";padding:0 2px 0 3px}
p a>code:hover{color:rgba(0,0,0,.9)}
#header,#content,#footnotes,#footer{width:100%;margin:0 auto;max-width:62.5em;*zoom:1;position:relative;padding-left:.9375em;padding-right:.9375em}
#header::before,#header::after,#content::before,#content::after,#footnotes::before,#footnotes::after,#footer::before,#footer::after{content:" ";display:table}
#header::after,#content::after,#footnotes::after,#footer::after{clear:both}
#content{margin-top:1.25em}
#content::before{content:none}
#header>h1:first-child{color:rgba(0,0,0,.85);margin-top:2.25rem;margin-bottom:0}
#header>h1:first-child+#toc{margin-top:8px;border-top:1px solid #dddddf}
#header>h1:only-child,body.toc2 #header>h1:nth-last-child(2){border-bottom:1px solid #dddddf;padding-bottom:8px}
#header .details{border-bottom:1px solid #dddddf;line-height:1.45;padding-top:.25em;padding-bottom:.25em;padding-left:.25em;color:rgba(0,0,0,.6);display:flex;flex-flow:row wrap}
#header .details span:first-child{margin-left:-.125em}
#header .details span.email a{color:rgba(0,0,0,.85)}
#header .details br{display:none}
#header .details br+span::before{content:"\00a0\2013\00a0"}
#header .details br+span.author::before{content:"\00a0\22c5\00a0";color:rgba(0,0,0,.85)}
#header .details br+span#revremark::before{content:"\00a0|\00a0"}
#header #revnumber{text-transform:capitalize}
#header #revnumber::after{content:"\00a0"}
#content>h1:first-child:not([class]){color:rgba(0,0,0,.85);border-bottom:1px solid #dddddf;padding-bottom:8px;margin-top:0;padding-top:1rem;margin-bottom:1.25rem}
#toc{border-bottom:1px solid #e7e7e9;padding-bottom:.5em}
#toc>ul{margin-left:.125em}
#toc ul.sectlevel0>li>a{font-style:italic}
#toc ul.sectlevel0 ul.sectlevel1{margin:.5em 0}
#toc ul{font-family:"Open Sans","DejaVu Sans",sans-serif;list-style-type:none}
#toc li{line-height:1.3334;margin-top:.3334em}
#toc a{text-decoration:none}
#toc a:active{text-decoration:underline}
#toctitle{color:#7a2518;font-size:1.2em}
@media screen and (min-width:768px){#toctitle{font-size:1.375em}
body.toc2{padding-left:15em;padding-right:0}
#toc.toc2{margin-top:0!important;background:#f8f8f7;position:fixed;width:15em;left:0;top:0;border-right:1px solid #e7e7e9;border-top-width:0!important;border-bottom-width:0!important;z-index:1000;padding:1.25em 1em;height:100%;overflow:auto}
#toc.toc2 #toctitle{margin-top:0;margin-bottom:.8rem;font-size:1.2em}
#toc.toc2>ul{font-size:.9em;margin-bottom:0}
#toc.toc2 ul ul{margin-left:0;padding-left:1em}
#toc.toc2 ul.sectlevel0 ul.sectlevel1{padding-left:0;margin-top:.5em;margin-bottom:.5em}
body.toc2.toc-right{padding-left:0;padding-right:15em}
body.toc2.toc-right #toc.toc2{border-right-width:0;border-left:1px solid #e7e7e9;left:auto;right:0}}
@media screen and (min-width:1280px){body.toc2{padding-left:20em;padding-right:0}
#toc.toc2{width:20em}
#toc.toc2 #toctitle{font-size:1.375em}
#toc.toc2>ul{font-size:.95em}
#toc.toc2 ul ul{padding-left:1.25em}
body.toc2.toc-right{padding-left:0;padding-right:20em}}
#content #toc{border:1px solid #e0e0dc;margin-bottom:1.25em;padding:1.25em;background:#f8f8f7;border-radius:4px}
#content #toc>:first-child{margin-top:0}
#content #toc>:last-child{margin-bottom:0}
#footer{max-width:none;background:rgba(0,0,0,.8);padding:1.25em}
#footer-text{color:hsla(0,0%,100%,.8);line-height:1.44}
#content{margin-bottom:.625em}
.sect1{padding-bottom:.625em}
@media screen and (min-width:768px){#content{margin-bottom:1.25em}
.sect1{padding-bottom:1.25em}}
.sect1:last-child{padding-bottom:0}
.sect1+.sect1{border-top:1px solid #e7e7e9}
#content h1>a.anchor,h2>a.anchor,h3>a.anchor,#toctitle>a.anchor,.sidebarblock>.content>.title>a.anchor,h4>a.anchor,h5>a.anchor,h6>a.anchor{position:absolute;z-index:1001;width:1.5ex;margin-left:-1.5ex;display:block;text-decoration:none!important;visibility:hidden;text-align:center;font-weight:400}
#content h1>a.anchor::before,h2>a.anchor::before,h3>a.anchor::before,#toctitle>a.anchor::before,.sidebarblock>.content>.title>a.anchor::before,h4>a.anchor::before,h5>a.anchor::before,h6>a.anchor::before{content:"\00A7";font-size:.85em;display:block;padding-top:.1em}
#content h1:hover>a.anchor,#content h1>a.anchor:hover,h2:hover>a.anchor,h2>a.anchor:hover,h3:hover>a.anchor,#toctitle:hover>a.anchor,.sidebarblock>.content>.title:hover>a.anchor,h3>a.anchor:hover,#toctitle>a.anchor:hover,.sidebarblock>.content>.title>a.anchor:hover,h4:hover>a.anchor,h4>a.anchor:hover,h5:hover>a.anchor,h5>a.anchor:hover,h6:hover>a.anchor,h6>a.anchor:hover{visibility:visible}
#content h1>a.link,h2>a.link,h3>a.link,#toctitle>a.link,.sidebarblock>.content>.title>a.link,h4>a.link,h5>a.link,h6>a.link{color:#ba3925;text-decoration:none}
#content h1>a.link:hover,h2>a.link:hover,h3>a.link:hover,#toctitle>a.link:hover,.sidebarblock>.content>.title>a.link:hover,h4>a.link:hover,h5>a.link:hover,h6>a.link:hover{color:#a53221}
details,.audioblock,.imageblock,.literalblock,.listingblock,.stemblock,.videoblock{margin-bottom:1.25em}
details{margin-left:1.25rem}
details>summary{cursor:pointer;display:block;position:relative;line-height:1.6;margin-bottom:.625rem;outline:none;-webkit-tap-highlight-color:transparent}
details>summary::-webkit-details-marker{display:none}
details>summary::before{content:"";border:solid transparent;border-left:solid;border-width:.3em 0 .3em .5em;position:absolute;top:.5em;left:-1.25rem;transform:translateX(15%)}
details[open]>summary::before{border:solid transparent;border-top:solid;border-width:.5em .3em 0;transform:translateY(15%)}
details>summary::after{content:"";width:1.25rem;height:1em;position:absolute;top:.3em;left:-1.25rem}
.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{text-rendering:optimizeLegibility;text-align:left;font-family:"Noto Serif","DejaVu Serif",serif;font-size:1rem;font-style:italic}
table.tableblock.fit-content>caption.title{white-space:nowrap;width:0}
.paragraph.lead>p,#preamble>.sectionbody>[class=paragraph]:first-of-type p{font-size:1.21875em;line-height:1.6;color:rgba(0,0,0,.85)}
.admonitionblock>table{border-collapse:separate;border:0;background:none;width:100%}
.admonitionblock>table td.icon{text-align:center;width:80px}
.admonitionblock>table td.icon img{max-width:none}
.admonitionblock>table td.icon .title{font-weight:bold;font-family:"Open Sans","DejaVu Sans",sans-serif;text-transform:uppercase}
.admonitionblock>table td.content{padding-left:1.125em;padding-right:1.25em;border-left:1px solid #dddddf;color:rgba(0,0,0,.6);word-wrap:anywhere}
.admonitionblock>table td.content>:last-child>:last-child{margin-bottom:0}
.exampleblock>.content{border:1px solid #e6e6e6;margin-bottom:1.25em;padding:1.25em;background:#fff;border-radius:4px}
.exampleblock>.content>:first-child{margin-top:0}
.exampleblock>.content>:last-child{margin-bottom:0}
.sidebarblock{border:1px solid #dbdbd6;margin-bottom:1.25em;padding:1.25em;background:#f3f3f2;border-radius:4px}
.sidebarblock>:first-child{margin-top:0}
.sidebarblock>:last-child{margin-bottom:0}
.sidebarblock>.content>.title{color:#7a2518;margin-top:0;text-align:center}
.exampleblock>.content>:last-child>:last-child,.exampleblock>.content .olist>ol>li:last-child>:last-child,.exampleblock>.content .ulist>ul>li:last-child>:last-child,.exampleblock>.content .qlist>ol>li:last-child>:last-child,.sidebarblock>.content>:last-child>:last-child,.sidebarblock>.content .olist>ol>li:last-child>:last-child,.sidebarblock>.content .ulist>ul>li:last-child>:last-child,.sidebarblock>.content .qlist>ol>li:last-child>:last-child{margin-bottom:0}
.literalblock pre,.listingblock>.content>pre{border-radius:4px;overflow-x:auto;padding:1em;font-size:.8125em}
@media screen and (min-width:768px){.literalblock pre,.listingblock>.content>pre{font-size:.90625em}}
@media screen and (min-width:1280px){.literalblock pre,.listingblock>.content>pre{font-size:1em}}
.literalblock pre,.listingblock>.content>pre:not(.highlight),.listingblock>.content>pre[class=highlight],.listingblock>.content>pre[class^="highlight "]{background:#f7f7f8}
.literalblock.output pre{color:#f7f7f8;background:rgba(0,0,0,.9)}
.listingblock>.content{position:relative}
.listingblock code[data-lang]::before{display:none;content:attr(data-lang);position:absolute;font-size:.75em;top:.425rem;right:.5rem;line-height:1;text-transform:uppercase;color:inherit;opacity:.5}
.listingblock:hover code[data-lang]::before{display:block}
.listingblock.terminal pre .command::before{content:attr(data-prompt);padding-right:.5em;color:inherit;opacity:.5}
.listingblock.terminal pre .command:not([data-prompt])::before{content:"$"}
.listingblock pre.highlightjs{padding:0}
.listingblock pre.highlightjs>code{padding:1em;border-radius:4px}
.listingblock pre.prettyprint{border-width:0}
.prettyprint{background:#f7f7f8}
pre.prettyprint .linenums{line-height:1.45;margin-left:2em}
pre.prettyprint li{background:none;list-style-type:inherit;padding-left:0}
pre.prettyprint li code[data-lang]::before{opacity:1}
pre.prettyprint li:not(:first-child) code[data-lang]::before{display:none}
table.linenotable{border-collapse:separate;border:0;margin-bottom:0;background:none}
table.linenotable td[class]{color:inherit;vertical-align:top;padding:0;line-height:inherit;white-space:normal}
table.linenotable td.code{padding-left:.75em}
table.linenotable td.linenos,pre.pygments .linenos{border-right:1px solid;opacity:.35;padding-right:.5em;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}
pre.pygments span.linenos{display:inline-block;margin-right:.75em}
.quoteblock{margin:0 1em 1.25em 1.5em;display:table}
.quoteblock:not(.excerpt)>.title{margin-left:-1.5em;margin-bottom:.75em}
.quoteblock blockquote,.quoteblock p{color:rgba(0,0,0,.85);font-size:1.15rem;line-height:1.75;word-spacing:.1em;letter-spacing:0;font-style:italic;text-align:justify}
.quoteblock blockquote{margin:0;padding:0;border:0}
.quoteblock blockquote::before{content:"\201c";float:left;font-size:2.75em;font-weight:bold;line-height:.6em;margin-left:-.6em;color:#7a2518;text-shadow:0 1px 2px rgba(0,0,0,.1)}
.quoteblock blockquote>.paragraph:last-child p{margin-bottom:0}
.quoteblock .attribution{margin-top:.75em;margin-right:.5ex;text-align:right}
.verseblock{margin:0 1em 1.25em}
.verseblock pre{font-family:"Open Sans","DejaVu Sans",sans-serif;font-size:1.15rem;color:rgba(0,0,0,.85);font-weight:300;text-rendering:optimizeLegibility}
.verseblock pre strong{font-weight:400}
.verseblock .attribution{margin-top:1.25rem;margin-left:.5ex}
.quoteblock .attribution,.verseblock .attribution{font-size:.9375em;line-height:1.45;font-style:italic}
.quoteblock .attribution br,.verseblock .attribution br{display:none}
.quoteblock .attribution cite,.verseblock .attribution cite{display:block;letter-spacing:-.025em;color:rgba(0,0,0,.6)}
.quoteblock.abstract blockquote::before,.quoteblock.excerpt blockquote::before,.quoteblock .quoteblock blockquote::before{display:none}
.quoteblock.abstract blockquote,.quoteblock.abstract p,.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{line-height:1.6;word-spacing:0}
.quoteblock.abstract{margin:0 1em 1.25em;display:block}
.quoteblock.abstract>.title{margin:0 0 .375em;font-size:1.15em;text-align:center}
.quoteblock.excerpt>blockquote,.quoteblock .quoteblock{padding:0 0 .25em 1em;border-left:.25em solid #dddddf}
.quoteblock.excerpt,.quoteblock .quoteblock{margin-left:0}
.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{color:inherit;font-size:1.0625rem}
.quoteblock.excerpt .attribution,.quoteblock .quoteblock .attribution{color:inherit;font-size:.85rem;text-align:left;margin-right:0}
p.tableblock:last-child{margin-bottom:0}
td.tableblock>.content{margin-bottom:1.25em;word-wrap:anywhere}
td.tableblock>.content>:last-child{margin-bottom:-1.25em}
table.tableblock,th.tableblock,td.tableblock{border:0 solid #dedede}
table.grid-all>*>tr>*{border-width:1px}
table.grid-cols>*>tr>*{border-width:0 1px}
table.grid-rows>*>tr>*{border-width:1px 0}
table.frame-all{border-width:1px}
table.frame-ends{border-width:1px 0}
table.frame-sides{border-width:0 1px}
table.frame-none>colgroup+*>:first-child>*,table.frame-sides>colgroup+*>:first-child>*{border-top-width:0}
table.frame-none>:last-child>:last-child>*,table.frame-sides>:last-child>:last-child>*{border-bottom-width:0}
table.frame-none>*>tr>:first-child,table.frame-ends>*>tr>:first-child{border-left-width:0}
table.frame-none>*>tr>:last-child,table.frame-ends>*>tr>:last-child{border-right-width:0}
table.stripes-all>*>tr,table.stripes-odd>*>tr:nth-of-type(odd),table.stripes-even>*>tr:nth-of-type(even),table.stripes-hover>*>tr:hover{background:#f8f8f7}
th.halign-left,td.halign-left{text-align:left}
th.halign-right,td.halign-right{text-align:right}
th.halign-center,td.halign-center{text-align:center}
th.valign-top,td.valign-top{vertical-align:top}
th.valign-bottom,td.valign-bottom{vertical-align:bottom}
th.valign-middle,td.valign-middle{vertical-align:middle}
table thead th,table tfoot th{font-weight:bold}
tbody tr th{background:#f7f8f7}
tbody tr th,tbody tr th p,tfoot tr th,tfoot tr th p{color:rgba(0,0,0,.8);font-weight:bold}
p.tableblock>code:only-child{background:none;padding:0}
p.tableblock{font-size:1em}
ol{margin-left:1.75em}
ul li ol{margin-left:1.5em}
dl dd{margin-left:1.125em}
dl dd:last-child,dl dd:last-child>:last-child{margin-bottom:0}
li p,ul dd,ol dd,.olist .olist,.ulist .ulist,.ulist .olist,.olist .ulist{margin-bottom:.625em}
ul.checklist,ul.none,ol.none,ul.no-bullet,ol.no-bullet,ol.unnumbered,ul.unstyled,ol.unstyled{list-style-type:none}
ul.no-bullet,ol.no-bullet,ol.unnumbered{margin-left:.625em}
ul.unstyled,ol.unstyled{margin-left:0}
li>p:empty:only-child::before{content:"";display:inline-block}
ul.checklist>li>p:first-child{margin-left:-1em}
ul.checklist>li>p:first-child>.fa-square-o:first-child,ul.checklist>li>p:first-child>.fa-check-square-o:first-child{width:1.25em;font-size:.8em;position:relative;bottom:.125em}
ul.checklist>li>p:first-child>input[type=checkbox]:first-child{margin-right:.25em}
ul.inline{display:flex;flex-flow:row wrap;list-style:none;margin:0 0 .625em -1.25em}
ul.inline>li{margin-left:1.25em}
.unstyled dl dt{font-weight:400;font-style:normal}
ol.arabic{list-style-type:decimal}
ol.decimal{list-style-type:decimal-leading-zero}
ol.loweralpha{list-style-type:lower-alpha}
ol.upperalpha{list-style-type:upper-alpha}
ol.lowerroman{list-style-type:lower-roman}
ol.upperroman{list-style-type:upper-roman}
ol.lowergreek{list-style-type:lower-greek}
.hdlist>table,.colist>table{border:0;background:none}
.hdlist>table>tbody>tr,.colist>table>tbody>tr{background:none}
td.hdlist1,td.hdlist2{vertical-align:top;padding:0 .625em}
td.hdlist1{font-weight:bold;padding-bottom:1.25em}
td.hdlist2{word-wrap:anywhere}
.literalblock+.colist,.listingblock+.colist{margin-top:-.5em}
.colist td:not([class]):first-child{padding:.4em .75em 0;line-height:1;vertical-align:top}
.colist td:not([class]):first-child img{max-width:none}
.colist td:not([class]):last-child{padding:.25em 0}
.thumb,.th{line-height:0;display:inline-block;border:4px solid #fff;box-shadow:0 0 0 1px #ddd}
.imageblock.left{margin:.25em .625em 1.25em 0}
.imageblock.right{margin:.25em 0 1.25em .625em}
.imageblock>.title{margin-bottom:0}
.imageblock.thumb,.imageblock.th{border-width:6px}
.imageblock.thumb>.title,.imageblock.th>.title{padding:0 .125em}
.image.left,.image.right{margin-top:.25em;margin-bottom:.25em;display:inline-block;line-height:0}
.image.left{margin-right:.625em}
.image.right{margin-left:.625em}
a.image{text-decoration:none;display:inline-block}
a.image object{pointer-events:none}
sup.footnote,sup.footnoteref{font-size:.875em;position:static;vertical-align:super}
sup.footnote a,sup.footnoteref a{text-decoration:none}
sup.footnote a:active,sup.footnoteref a:active{text-decoration:underline}
#footnotes{padding-top:.75em;padding-bottom:.75em;margin-bottom:.625em}
#footnotes hr{width:20%;min-width:6.25em;margin:-.25em 0 .75em;border-width:1px 0 0}
#footnotes .footnote{padding:0 .375em 0 .225em;line-height:1.3334;font-size:.875em;margin-left:1.2em;margin-bottom:.2em}
#footnotes .footnote a:first-of-type{font-weight:bold;text-decoration:none;margin-left:-1.05em}
#footnotes .footnote:last-of-type{margin-bottom:0}
#content #footnotes{margin-top:-.625em;margin-bottom:0;padding:.75em 0}
div.unbreakable{page-break-inside:avoid}
.big{font-size:larger}
.small{font-size:smaller}
.underline{text-decoration:underline}
.overline{text-decoration:overline}
.line-through{text-decoration:line-through}
.aqua{color:#00bfbf}
.aqua-background{background:#00fafa}
.black{color:#000}
.black-background{background:#000}
.blue{color:#0000bf}
.blue-background{background:#0000fa}
.fuchsia{color:#bf00bf}
.fuchsia-background{background:#fa00fa}
.gray{color:#606060}
.gray-background{background:#7d7d7d}
.green{color:#006000}
.green-background{background:#007d00}
.lime{color:#00bf00}
.lime-background{background:#00fa00}
.maroon{color:#600000}
.maroon-background{background:#7d0000}
.navy{color:#000060}
.navy-background{background:#00007d}
.olive{color:#606000}
.olive-background{background:#7d7d00}
.purple{color:#600060}
.purple-background{background:#7d007d}
.red{color:#bf0000}
.red-background{background:#fa0000}
.silver{color:#909090}
.silver-background{background:#bcbcbc}
.teal{color:#006060}
.teal-background{background:#007d7d}
.white{color:#bfbfbf}
.white-background{background:#fafafa}
.yellow{color:#bfbf00}
.yellow-background{background:#fafa00}
span.icon>.fa{cursor:default}
a span.icon>.fa{cursor:inherit}
.admonitionblock td.icon [class^="fa icon-"]{font-size:2.5em;text-shadow:1px 1px 2px rgba(0,0,0,.5);cursor:default}
.admonitionblock td.icon .icon-note::before{content:"\f05a";color:#19407c}
.admonitionblock td.icon .icon-tip::before{content:"\f0eb";text-shadow:1px 1px 2px rgba(155,155,0,.8);color:#111}
.admonitionblock td.icon .icon-warning::before{content:"\f071";color:#bf6900}
.admonitionblock td.icon .icon-caution::before{content:"\f06d";color:#bf3400}
.admonitionblock td.icon .icon-important::before{content:"\f06a";color:#bf0000}
.conum[data-value]{display:inline-block;color:#fff!important;background:rgba(0,0,0,.8);border-radius:50%;text-align:center;font-size:.75em;width:1.67em;height:1.67em;line-height:1.67em;font-family:"Open Sans","DejaVu Sans",sans-serif;font-style:normal;font-weight:bold}
.conum[data-value] *{color:#fff!important}
.conum[data-value]+b{display:none}
.conum[data-value]::after{content:attr(data-value)}
pre .conum[data-value]{position:relative;top:-.125em}
b.conum *{color:inherit!important}
.conum:not([data-value]):empty{display:none}
dt,th.tableblock,td.content,div.footnote{text-rendering:optimizeLegibility}
h1,h2,p,td.content,span.alt,summary{letter-spacing:-.01em}
p strong,td.content strong,div.footnote strong{letter-spacing:-.005em}
p,blockquote,dt,td.content,span.alt,summary{font-size:1.0625rem}
p{margin-bottom:1.25rem}
.sidebarblock p,.sidebarblock dt,.sidebarblock td.content,p.tableblock{font-size:1em}
.exampleblock>.content{background:#fffef7;border-color:#e0e0dc;box-shadow:0 1px 4px #e0e0dc}
.print-only{display:none!important}
@page{margin:1.25cm .75cm}
@media print{*{box-shadow:none!important;text-shadow:none!important}
html{font-size:80%}
a{color:inherit!important;text-decoration:underline!important}
a.bare,a[href^="#"],a[href^="mailto:"]{text-decoration:none!important}
a[href^="http:"]:not(.bare)::after,a[href^="https:"]:not(.bare)::after{content:"(" attr(href) ")";display:inline-block;font-size:.875em;padding-left:.25em}
abbr[title]{border-bottom:1px dotted}
abbr[title]::after{content:" (" attr(title) ")"}
pre,blockquote,tr,img,object,svg{page-break-inside:avoid}
thead{display:table-header-group}
svg{max-width:100%}
p,blockquote,dt,td.content{font-size:1em;orphans:3;widows:3}
h2,h3,#toctitle,.sidebarblock>.content>.title{page-break-after:avoid}
#header,#content,#footnotes,#footer{max-width:none}
#toc,.sidebarblock,.exampleblock>.content{background:none!important}
#toc{border-bottom:1px solid #dddddf!important;padding-bottom:0!important}
body.book #header{text-align:center}
body.book #header>h1:first-child{border:0!important;margin:2.5em 0 1em}
body.book #header .details{border:0!important;display:block;padding:0!important}
body.book #header .details span:first-child{margin-left:0!important}
body.book #header .details br{display:block}
body.book #header .details br+span::before{content:none!important}
body.book #toc{border:0!important;text-align:left!important;padding:0!important;margin:0!important}
body.book #toc,body.book #preamble,body.book h1.sect0,body.book .sect1>h2{page-break-before:always}
.listingblock code[data-lang]::before{display:block}
#footer{padding:0 .9375em}
.hide-on-print{display:none!important}
.print-only{display:block!important}
.hide-for-print{display:none!important}
.show-for-print{display:inherit!important}}
@media amzn-kf8,print{#header>h1:first-child{margin-top:1.25rem}
.sect1{padding:0!important}
.sect1+.sect1{border:0}
#footer{background:none}
#footer-text{color:rgba(0,0,0,.6);font-size:.9em}}
@media amzn-kf8{#header,#content,#footnotes,#footer{padding:0}}
</style>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style>
/*! Stylesheet for CodeRay to loosely match GitHub themes | MIT License */
pre.CodeRay{background:#f7f7f8}
.CodeRay .line-numbers{border-right:1px solid;opacity:.35;padding:0 .5em 0 0;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}
.CodeRay span.line-numbers{display:inline-block;margin-right:.75em}
.CodeRay .line-numbers strong{color:#000}
table.CodeRay{border-collapse:separate;border:0;margin-bottom:0;background:none}
table.CodeRay td{vertical-align:top;line-height:inherit}
table.CodeRay td.line-numbers{text-align:right}
table.CodeRay td.code{padding:0 0 0 .75em}
.CodeRay .debug{color:#fff!important;background:navy!important}
.CodeRay .annotation{color:#007}
.CodeRay .attribute-name{color:navy}
.CodeRay .attribute-value{color:#700}
.CodeRay .binary{color:#509}
.CodeRay .comment{color:#998;font-style:italic}
.CodeRay .char{color:#04d}
.CodeRay .char .content{color:#04d}
.CodeRay .char .delimiter{color:#039}
.CodeRay .class{color:#458;font-weight:bold}
.CodeRay .complex{color:#a08}
.CodeRay .constant,.CodeRay .predefined-constant{color:teal}
.CodeRay .color{color:#099}
.CodeRay .class-variable{color:#369}
.CodeRay .decorator{color:#b0b}
.CodeRay .definition{color:#099}
.CodeRay .delimiter{color:#000}
.CodeRay .doc{color:#970}
.CodeRay .doctype{color:#34b}
.CodeRay .doc-string{color:#d42}
.CodeRay .escape{color:#666}
.CodeRay .entity{color:#800}
.CodeRay .error{color:#808}
.CodeRay .exception{color:inherit}
.CodeRay .filename{color:#099}
.CodeRay .function{color:#900;font-weight:bold}
.CodeRay .global-variable{color:teal}
.CodeRay .hex{color:#058}
.CodeRay .integer,.CodeRay .float{color:#099}
.CodeRay .include{color:#555}
.CodeRay .inline{color:#000}
.CodeRay .inline .inline{background:#ccc}
.CodeRay .inline .inline .inline{background:#bbb}
.CodeRay .inline .inline-delimiter{color:#d14}
.CodeRay .inline-delimiter{color:#d14}
.CodeRay .important{color:#555;font-weight:bold}
.CodeRay .interpreted{color:#b2b}
.CodeRay .instance-variable{color:teal}
.CodeRay .label{color:#970}
.CodeRay .local-variable{color:#963}
.CodeRay .octal{color:#40e}
.CodeRay .predefined{color:#369}
.CodeRay .preprocessor{color:#579}
.CodeRay .pseudo-class{color:#555}
.CodeRay .directive{font-weight:bold}
.CodeRay .type{font-weight:bold}
.CodeRay .predefined-type{color:inherit}
.CodeRay .reserved,.CodeRay .keyword{color:#000;font-weight:bold}
.CodeRay .key{color:#808}
.CodeRay .key .delimiter{color:#606}
.CodeRay .key .char{color:#80f}
.CodeRay .value{color:#088}
.CodeRay .regexp .delimiter{color:#808}
.CodeRay .regexp .content{color:#808}
.CodeRay .regexp .modifier{color:#808}
.CodeRay .regexp .char{color:#d14}
.CodeRay .regexp .function{color:#404;font-weight:bold}
.CodeRay .string{color:#d20}
.CodeRay .string .string .string{background:#ffd0d0}
.CodeRay .string .content{color:#d14}
.CodeRay .string .char{color:#d14}
.CodeRay .string .delimiter{color:#d14}
.CodeRay .shell{color:#d14}
.CodeRay .shell .delimiter{color:#d14}
.CodeRay .symbol{color:#990073}
.CodeRay .symbol .content{color:#a60}
.CodeRay .symbol .delimiter{color:#630}
.CodeRay .tag{color:teal}
.CodeRay .tag-special{color:#d70}
.CodeRay .variable{color:#036}
.CodeRay .insert{background:#afa}
.CodeRay .delete{background:#faa}
.CodeRay .change{color:#aaf;background:#007}
.CodeRay .head{color:#f8f;background:#505}
.CodeRay .insert .insert{color:#080}
.CodeRay .delete .delete{color:#800}
.CodeRay .change .change{color:#66f}
.CodeRay .head .head{color:#f4f}
</style>
</head>
<body id="High_Availability_Guide" class="book toc2 toc-left">
<div id="header">
<h1>High Availability Guide</h1>
<div class="details">
<span id="author" class="author">WildFly clustering team</span><br>
<span id="revnumber">version 27.0.0.Final,</span>
<span id="revdate">2022-11-08T01:15:58Z</span>
</div>
<div id="toc" class="toc2">
<div id="toctitle">High Availability Guide</div>
<ul class="sectlevel1">
<li><a href="#Introduction_To_High_Availability_Services">1. Introduction To High Availability Services</a>
<ul class="sectlevel2">
<li><a href="#what-are-high-availability-services">1.1. What are High Availability services?</a></li>
<li><a href="#high-availability-through-fail-over">1.2. High Availability through fail-over</a></li>
<li><a href="#high-availability-through-load-balancing">1.3. High Availability through load balancing</a></li>
<li><a href="#aims-of-the-guide">1.4. Aims of the guide</a></li>
<li><a href="#organization-of-the-guide">1.5. Organization of the guide</a></li>
</ul>
</li>
<li><a href="#Distributable_Web_Applications">2. Distributable Web Applications</a>
<ul class="sectlevel2">
<li><a href="#distributable-web-subsystem">2.1. Distributable Web Subsystem</a>
<ul class="sectlevel3">
<li><a href="#infinispan-session-management">2.1.1. Infinispan session management</a></li>
<li><a href="#hotrod-session-management">2.1.2. HotRod session management</a></li>
</ul>
</li>
<li><a href="#overriding-default-behavior">2.2. Overriding default behavior</a>
<ul class="sectlevel3">
<li><a href="#referencing-an-existing-session-management-profile">2.2.1. Referencing an existing session management profile</a></li>
<li><a href="#using-a-deployment-specific-session-management-profile">2.2.2. Using a deployment-specific session management profile</a></li>
</ul>
</li>
<li><a href="#distributable-shared-sessions">2.3. Distributable Shared Sessions</a></li>
<li><a href="#optimizing-performance-of-distributed-web-applications">2.4. Optimizing performance of distributed web applications</a>
<ul class="sectlevel3">
<li><a href="#session_granularity">2.4.1. Session granularity</a></li>
<li><a href="#session_concurrency">2.4.2. Session concurrency</a></li>
<li><a href="#session_attribute_immutability">2.4.3. Session attribute immutability</a></li>
<li><a href="#session_attribute_marshalling">2.4.4. Session attribute marshalling</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#Distributable_Jakarta_Enterprise_Beans_Applications">3. Distributable Jakarta Enterprise Beans Applications</a>
<ul class="sectlevel2">
<li><a href="#distributable-ejb-subsystem">3.1. Distributable EJB Subsystem</a>
<ul class="sectlevel3">
<li><a href="#bean-management-providers">3.1.1. Bean management providers</a></li>
<li><a href="#client-mappings-registries">3.1.2. Client mappings registries</a></li>
<li><a href="#timer-management">3.1.3. Timer management</a></li>
</ul>
</li>
<li><a href="#deploying-clustered-ejbs">3.2. Deploying clustered EJBs</a>
<ul class="sectlevel3">
<li><a href="#failover-for-clustered-ejbs">3.2.1. Failover for clustered EJBs</a></li>
<li><a href="#remote-standalone-clients">3.2.2. Remote standalone clients</a></li>
<li><a href="#cluster-topology-communication">3.2.3. Cluster topology communication</a></li>
<li><a href="#remote-clients-on-another-instance">3.2.4. Remote clients on another instance of WildFly</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#messaging">4. Messaging</a></li>
<li><a href="#load-balancing">5. Load Balancing</a>
<ul class="sectlevel2">
<li><a href="#mod_cluster_Subsystem">5.1. mod_cluster Subsystem</a>
<ul class="sectlevel3">
<li><a href="#mod_cluster_subsystem_configuration">5.1.1. Configuration</a></li>
<li><a href="#runtime-operations">5.1.2. Runtime Operations</a></li>
<li><a href="#SSL_Configuration_using_Elytron_Subsystem">5.1.3. SSL Configuration using Elytron Subsystem</a></li>
<li><a href="#remote-user-authentication-with-elytron">5.1.4. Remote User Authentication with Elytron</a></li>
</ul>
</li>
<li><a href="#ranked-affinity-load-balancer">5.2. Enabling ranked affinity support in load balancer</a></li>
</ul>
</li>
<li><a href="#HA_Singleton_Features">6. HA Singleton Features</a>
<ul class="sectlevel2">
<li><a href="#Singleton_subsystem">6.1. Singleton subsystem</a>
<ul class="sectlevel3">
<li><a href="#singleton-configuration">6.1.1. Configuration</a></li>
<li><a href="#non-ha-environments">6.1.2. Non-HA environments</a></li>
</ul>
</li>
<li><a href="#Singleton_deployments">6.2. Singleton deployments</a>
<ul class="sectlevel3">
<li><a href="#usage-singleton-deployments">6.2.1. Usage</a></li>
<li><a href="#singleton-deployment-metrics">6.2.2. Singleton Deployment metrics</a></li>
</ul>
</li>
<li><a href="#Singleton_MSC_services">6.3. Singleton MSC services</a>
<ul class="sectlevel3">
<li><a href="#installing-an-msc-service-using-an-existing-singleton-policy">6.3.1. Installing an MSC service using an existing singleton policy</a></li>
<li><a href="#singleton-msc-service-metrics">6.3.2. Singleton MSC Service metrics</a></li>
<li><a href="#installing-an-msc-service-using-dynamic-singleton-policy">6.3.3. Installing an MSC service using dynamic singleton policy</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#Clustering_API">7. Clustering API</a>
<ul class="sectlevel2">
<li><a href="#group">7.1. Group membership</a>
<ul class="sectlevel3">
<li><a href="#node">7.1.1. Node</a></li>
<li><a href="#membership">7.1.2. Membership</a></li>
<li><a href="#usage">7.1.3. Usage</a></li>
<li><a href="#example">7.1.4. Example</a></li>
</ul>
</li>
<li><a href="#command-dispatcher">7.2. Command Dispatcher</a>
<ul class="sectlevel3">
<li><a href="#commanddispatcherfactory">7.2.1. CommandDispatcherFactory</a></li>
<li><a href="#command">7.2.2. Command</a></li>
<li><a href="#commanddispatcher">7.2.3. CommandDispatcher</a></li>
<li><a href="#example-2">7.2.4. Example</a></li>
</ul>
</li>
<li><a href="#service-provider-registry">7.3. Service Provider Registry</a>
<ul class="sectlevel3">
<li><a href="#example-3">7.3.1. Example</a></li>
</ul>
</li>
<li><a href="#registry">7.4. Registry</a>
<ul class="sectlevel3">
<li><a href="#example-4">7.4.1. Example</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#jgroups">8. JGroups</a>
<ul class="sectlevel2">
<li><a href="#JGroups_Subsystem">8.1. JGroups Subsystem</a>
<ul class="sectlevel3">
<li><a href="#jgroups-purpose">8.1.1. Purpose</a></li>
<li><a href="#jgroups-configuration-example">8.1.2. Configuration example</a></li>
<li><a href="#jgroups-use-cases">8.1.3. Use Cases</a></li>
</ul>
</li>
<li><a href="#member-discovery">8.2. Member Discovery</a>
<ul class="sectlevel3">
<li><a href="#discovery-for-kubernetes">8.2.1. Discovery for Kubernetes</a></li>
<li><a href="#discovery-for-aws-ec2">8.2.2. Discovery for AWS EC2</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#infinispan">9. Infinispan</a>
<ul class="sectlevel2">
<li><a href="#Infinispan_Subsystem">9.1. Infinispan Subsystem</a>
<ul class="sectlevel3">
<li><a href="#cache-container">9.1.1. Cache container</a></li>
<li><a href="#remote_cache_container">9.1.2. Remote Cache Container</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#advanced-topics">10. Advanced Topics</a>
<ul class="sectlevel2">
<li><a href="#marshalling">10.1. Marshalling</a>
<ul class="sectlevel3">
<li><a href="#jboss_marshalling">10.1.1. JBoss Marshalling</a></li>
<li><a href="#protostream">10.1.2. ProtoStream</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#Clustering_and_Domain_Setup_Walkthrough">11. Clustering and Domain Setup Walkthrough</a>
<ul class="sectlevel2">
<li><a href="#preparation-scenario">11.1. Preparation & Scenario</a>
<ul class="sectlevel3">
<li><a href="#preparation">11.1.1. Preparation</a></li>
<li><a href="#scenario">11.1.2. Scenario</a></li>
</ul>
</li>
<li><a href="#download-wildfly">11.2. Download WildFly</a></li>
<li><a href="#domain-configuration">11.3. Domain Configuration</a>
<ul class="sectlevel3">
<li><a href="#interface-config-on-primary-hc">11.3.1. Interface config on the Primary Host Controller</a></li>
<li><a href="#interface-config-on-secondary-hc">11.3.2. Interface config on the Secondary Host Controller</a></li>
</ul>
</li>
<li><a href="#deployment">11.4. Deployment</a></li>
<li><a href="#cluster-configuration">11.5. Cluster Configuration</a></li>
<li><a href="#testing">11.6. Testing</a></li>
<li><a href="#special-thanks">11.7. Special Thanks</a></li>
</ul>
</li>
</ul>
</div>
</div>
<div id="content">
<div id="preamble">
<div class="sectionbody">
<div class="paragraph">
<p>© 2017–2022 The original authors.</p>
</div>
<!-- toc disabled -->
</div>
</div>
<div class="sect1">
<h2 id="Introduction_To_High_Availability_Services"><a class="anchor" href="#Introduction_To_High_Availability_Services"></a>1. Introduction To High Availability Services</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="what-are-high-availability-services"><a class="anchor" href="#what-are-high-availability-services"></a>1.1. What are High Availability services?</h3>
<div class="paragraph">
<p>WildFly’s High Availability services are used to guarantee availability
of a deployed Jakarta EE application.</p>
</div>
<div class="paragraph">
<p>Deploying critical applications on a single node suffers from two
potential problems:</p>
</div>
<div class="ulist">
<ul>
<li>
<p>loss of application availability when the node hosting the application
crashes (single point of failure)</p>
</li>
<li>
<p>loss of application availability in the form of extreme delays in
response time during high volumes of requests (overwhelmed server)</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>WildFly supports two features which ensure high availability of critical
Jakarta EE applications:</p>
</div>
<div class="ulist">
<ul>
<li>
<p><strong>fail-over:</strong> allows a client interacting with a Jakarta EE application to
have uninterrupted access to that application, even in the presence of
node failures</p>
</li>
<li>
<p><strong>load balancing:</strong> allows a client to have timely responses from the
application, even in the presence of high-volumes of requests</p>
</li>
</ul>
</div>
<div class="admonitionblock important">
<table>
<tr>
<td class="icon">
<i class="fa icon-important" title="Important"></i>
</td>
<td class="content">
These two independent high availability services can very effectively
inter-operate when making use of mod_cluster for load balancing!
</td>
</tr>
</table>
</div>
<div class="paragraph">
<p>Taking advantage of WildFly’s high availability services is easy, and
simply involves deploying WildFly on a cluster of nodes, making a small
number of application configuration changes, and then deploying the
application in the cluster.</p>
</div>
<div class="paragraph">
<p>We now take a brief look at what these services can guarantee.</p>
</div>
</div>
<div class="sect2">
<h3 id="high-availability-through-fail-over"><a class="anchor" href="#high-availability-through-fail-over"></a>1.2. High Availability through fail-over</h3>
<div class="paragraph">
<p>Fail-over allows a client interacting with a Jakarta EE application to have
uninterrupted access to that application, even in the presence of node
failures. For example, consider a Jakarta EE application which makes use of
the following features:</p>
</div>
<div class="ulist">
<ul>
<li>
<p>session-oriented servlets to provide user interaction</p>
</li>
<li>
<p>session-oriented Jakarta Enterprise Beans to perform state-dependent business computation</p>
</li>
<li>
<p>Jakarta Enterprise Beans entity beans to store critical data in a persistent store (e.g.
database)</p>
</li>
<li>
<p>SSO login to the application</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>If the application makes use of WildFly’s fail-over services, a client
interacting with an instance of that application will not be interrupted
even when the node on which that instance executes crashes. Behind the
scenes, WildFly makes sure that all of the user data that the
application make use of (HTTP session data, Jakarta Enterprise Beans SFSB sessions,
Jakarta Enterprise Beans entities and SSO credentials) are available at other nodes in the
cluster, so that when a failure occurs and the client is redirected to
that new node for continuation of processing (i.e. the client "fails
over" to the new node), the user’s data is available and processing can
continue.</p>
</div>
<div class="paragraph">
<p>The Infinispan and JGroups subsystems are instrumental in providing
these data availability guarantees and will be discussed in detail later
in the guide.</p>
</div>
</div>
<div class="sect2">
<h3 id="high-availability-through-load-balancing"><a class="anchor" href="#high-availability-through-load-balancing"></a>1.3. High Availability through load balancing</h3>
<div class="paragraph">
<p>Load balancing enables the application to respond to client requests in
a timely fashion, even when subjected to a high-volume of requests.
Using a load balancer as a front-end, each incoming HTTP request can be
directed to one node in the cluster for processing. In this way, the
cluster acts as a pool of processing nodes and the load is "balanced"
over the pool, achieving scalability and, as a consequence,
availability. Requests involving session-oriented servlets are directed
to the the same application instance in the pool for efficiency of
processing (sticky sessions). Using mod_cluster has the advantage that
changes in cluster topology (scaling the pool up or down, servers
crashing) are communicated back to the load balancer and used to update
in real time the load balancing activity and avoid requests being
directed to application instances which are no longer available.</p>
</div>
<div class="paragraph">
<p>The mod_cluster subsystem is instrumental in providing support for this
High Availability feature of WildFly and will be discussed in detail
later in this guide.</p>
</div>
</div>
<div class="sect2">
<h3 id="aims-of-the-guide"><a class="anchor" href="#aims-of-the-guide"></a>1.4. Aims of the guide</h3>
<div class="paragraph">
<p>This guide aims to:</p>
</div>
<div class="ulist">
<ul>
<li>
<p>provide a description of the high-availability features available in
WildFly and the services they depend on</p>
</li>
<li>
<p>show how the various high availability services can be configured for
particular application use cases</p>
</li>
<li>
<p>identify default behavior for features relating to
high-availability/clustering</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="organization-of-the-guide"><a class="anchor" href="#organization-of-the-guide"></a>1.5. Organization of the guide</h3>
<div class="paragraph">
<p>As high availability features and their configuration depend on the
particular component they affect (e.g. HTTP sessions, Jakarta Enterprise Beans SFSB sessions,
Hibernate), we organize the discussion around those Jakarta EE features. We
strive to make each section as self-contained as possible. Also, when
discussing a feature, we will introduce any WildFly subsystems upon
which the feature depends.</p>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="Distributable_Web_Applications"><a class="anchor" href="#Distributable_Web_Applications"></a>2. Distributable Web Applications</h2>
<div class="sectionbody">
<div class="paragraph">
<p>In a standard web application, session state does not survive beyond the lifespan of the servlet container.
A distributable web application allows session state to survive beyond the lifespan of a single server, either via persistence or by replicating state to other nodes in the cluster.
A web application indicates its intention to be distributable via the <code><distributable/></code> element within the web application’s deployment descriptor.</p>
</div>
<div class="paragraph">
<p>e.g.</p>
</div>
<div class="listingblock">
<div class="title">/WEB-INF/web.xml:</div>
<div class="content">
<pre class="CodeRay highlight"><code data-lang="xml"><span class="tag"><web-app</span> <span class="attribute-name">xmlns</span>=<span class="string"><span class="delimiter">"</span><span class="content">http://xmlns.jcp.org/xml/ns/javaee</span><span class="delimiter">"</span></span>
<span class="attribute-name">xmlns:xsi</span>=<span class="string"><span class="delimiter">"</span><span class="content">http://www.w3.org/2001/XMLSchema-instance</span><span class="delimiter">"</span></span>
<span class="attribute-name">xsi:schemaLocation</span>=<span class="string"><span class="delimiter">"</span><span class="content">http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd</span><span class="delimiter">"</span></span>
<span class="attribute-name">version</span>=<span class="string"><span class="delimiter">"</span><span class="content">4.0</span><span class="delimiter">"</span></span><span class="tag">></span>
<span class="tag"><distributable</span><span class="tag">/></span>
<span class="tag"></web-app></span></code></pre>
</div>
</div>
<div class="sect2">
<h3 id="distributable-web-subsystem"><a class="anchor" href="#distributable-web-subsystem"></a>2.1. Distributable Web Subsystem</h3>
<div class="paragraph">
<p>The distributable-web subsystem manages a set of session management profiles that encapsulate the configuration of a distributable session manager.
One of these profiles will be designated as the default profile (via the "default-session-management" attribute) and thus defines the default behavior of a distributable web application.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight"><code>[standalone@embedded /] /subsystem=distributable-web:read-attribute(name=default-session-management)
{
"outcome" => "success",
"result" => "default"
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>The default session management stores web session data within an Infinispan cache.
We can introspect its configuration:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight"><code>[standalone@embedded /] /subsystem=distributable-web/infinispan-session-management=default:read-resource
{
"outcome" => "success",
"result" => {
"cache" => undefined,
"cache-container" => "web",
"granularity" => "SESSION",
"affinity" => {"primary-owner" => undefined}
}
}</code></pre>
</div>
</div>
<div class="sect3">
<h4 id="infinispan-session-management"><a class="anchor" href="#infinispan-session-management"></a>2.1.1. Infinispan session management</h4>
<div class="paragraph">
<p>The <code>infinispan-session-management</code> resource configures a distributable session manager that uses an embedded Infinispan cache.</p>
</div>
<div class="dlist">
<dl>
<dt class="hdlist1">cache-container</dt>
<dd>
<p>This references a cache-container defined in the Infinispan subsystem into which session data will be stored.</p>
</dd>
<dt class="hdlist1">cache</dt>
<dd>
<p>This references a cache within associated cache-container upon whose configuration the web application’s cache will be based.
If undefined, the default cache of the associated cache container will be used.</p>
</dd>
<dt class="hdlist1">granularity</dt>
<dd>
<p>This defines how the session manager will map a session into individual cache entries.
Possible values are:</p>
<div class="dlist">
<dl>
<dt class="hdlist1">SESSION</dt>
<dd>
<p>Stores all session attributes within a single cache entry.
This is generally more expensive than ATTRIBUTE granularity, but preserves any cross-attribute object references.</p>
</dd>
<dt class="hdlist1">ATTRIBUTE</dt>
<dd>
<p>Stores each session attribute within a separate cache entry.
This is generally more efficient than SESSION granularity, but does not preserve any cross-attribute object references.</p>
</dd>
</dl>
</div>
</dd>
<dt class="hdlist1">affinity</dt>
<dd>
<p>This resource defines the affinity that a web request should have for a given server.
The affinity of the associated web session determines the algorithm for generating the route to be appended onto the session ID (within the JSESSIONID cookie, or when encoding URLs).
This annotation of the session ID is used by load balancers to advise how future requests for existing sessions should be directed.
Routing is designed to be opaque to application code such that calls to <code>HttpSession.getId()</code> always return an unmodified session ID.
This is only generated when creating/updating the JSESSIONID cookie, or when encoding URLs via <code>HttpServletResponse.encodeURL()</code> and <code>encodeRedirectURL()</code>.
Possible values are:</p>
<div class="dlist">
<dl>
<dt class="hdlist1">affinity=none</dt>
<dd>
<p>Web requests will have no affinity to any particular node.
This option is intended for use cases where web session state is not maintained within the application server.</p>