`<div dir="ltr">This was a first for me and extremely painful to locate.<div><br></div><div>In the middle of the night between last Friday and Saturday, I started getting down alerts from most of my network. It took 4 engineers including myself 9 hours to pinpoint the source of the problem.</div><div><br></div><div>The problem turned out to be one of my OmniOS boxes sending out pure garbage constantly on layer 2 out the 10G network ports. This disrupted ARP caches on every machine on every VLAN that was trunked on these ports, not just the VLANs that were configured on the server. The switches reported every port healthy and without error. The traffic on the bad port was not high either, just severely disruptive.</div><div><br>The affected OmniOS box appear to be healthy, as it was still serving the VM data stores for over 350 virtual machines. However, it like every other service on the network appeared to be up and down repeatedly, but NFS kept on recovering gracefully.</div><div><br></div><div>The only thing that finally identified this server was when one of us plug a monitor to the console and saw "WARNING: proxy ARP problem?" happening so fast that it took taking a cellphone picture of it a high frame rate to read it. Powering off this server, cleared the problem for the entire network, and its pools were taken over by its HA sister.</div><div><br></div><div>Googling for that warning brings up nothing useful.</div><div><br></div><div>Has anyone ever seen a problem like this? How did you locate it?</div><div><br></div><div>-Chip</div><div><br></div></div>
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