EOS: Auto-generate unique system MAC for MLAG

[jbemmel]

According to https://arista.my.site.com/AristaCommunity/s/article/ceos-lab-in-gns3#Comm_Kna_ka08C0000008SDgQAM_05 cEOS needs a unique system mac for MLAG to work properly

If not provided by the user, Netlab should auto-generate one for clab nodes that use mlag

[ipspace]

containerlab takes care of that for a very long time (https://github.com/srl-labs/containerlab/blame/main/nodes/ceos/ceos.go#L200)

[jbemmel]

Two questions:

1. Re: b5489ff

"To make things worse, MLAG still worked on cEOS containers because they all have the same system MAC address :("

That's why the issue says unique ...

2. What about libvirt VMs?

[ipspace]

1. Re: b5489ff

"To make things worse, MLAG still worked on cEOS containers because they all have the same system MAC address :("

That was a bad knee-jerk response based on the title of this issue :( cEOS containers always had unique system MAC addresses because containerlab took care of that.

2. What about libvirt VMs?

Somehow they get unique system MAC addresses as well 🤷‍♂️