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macvlan and vr-based nodes

Open hellt opened this issue 2 years ago • 6 comments

It has been reported that vr-based nodes have datapath connectivity issue when using the macvlan mode.

Considering the following topology:

name: mvlantest


topology:
  kinds:
    vr-sros:
      image: vrnetlab/vr-sros:22.5.R1
      license: license-vsr-i-22.txt
 
  nodes:
    pe1:
      kind: vr-sros

  links:
    - endpoints: ["pe1:eth1", "macvlan:ens33"]

the following has been observed:

The ping replies initiated from vr node to an IP reachable from the macvlan segment do not propagate to the macvlan interface from the parent interface:

image

I think this might be related to the tc mirred redirect rules, which might require some tuning for macvlan interfaces?

hellt avatar Jan 10 '24 10:01 hellt

setting the macvlan mode to passthru solved this need to check if our default bridge mode must be switched to passthru

hellt avatar Jan 10 '24 11:01 hellt

Passthru: allows a single VM to be connected directly to the physical interface.

I don't think this is what we want?! I exposed the mode in the extensive version of the MacVlan link definition. So simply set it that way. https://containerlab.dev/manual/topo-def-file/#macvlan

steiler avatar Jan 10 '24 13:01 steiler

the question is why in bridge mode connectivity breaks, and what passthru does differently

hellt avatar Jan 10 '24 13:01 hellt