We 've recently noticed that the kubernetes codfw cluster has a steady rate of outdoing discarded packets. While not alarming, the very steady rate[1] of these errors is peculiar and warrants more investigation.
As per the graph below
the error rate is ~5 discarded packets per sec. These are outgoing packets. Digging into it some more it does seem that these are ICMP redirects.
We already found a bug in sysstat trying to follow up on this. See https://github.com/sysstat/sysstat/pull/226
It's worth noting that kubernetes
[1] https://grafana.wikimedia.org/d/000000366/network-performances-global