[LU-2418] Add Way to Detect Dropped Packets on Production Systems

• Type: Improvement
• Resolution: Unresolved
• Priority: Major
• Affects Version/s: Lustre 2.4.0
• Assignee: WC Triage
• Reporter: Doug Oucharek (Inactive)

Description

Today, it is very difficult to confirm whether timeouts in Lustre are due to dropped packets in LNet. This is due to two reasons:

1- neterrors are off by default so logging does not show dropped packets.
2- the errors counter is never incremented (see LU-2223).

My understanding is that neterrors are off by default because there is too much "noise" when they are on. That begs the question: how can logs which are issued that frequently be considered errors?

I think this issue can be address in one of two ways:

1- Clean up the neterror logs so they are not noisy and then leave neterrors on by default.
2- Add a set of new counters to LNet to count the reasons for dropped packets.

Issue Links

• duplicates: LU-8223 De-Noise LNet neterr logs so they can be ON by default