Diagnosing stray/stale .keep files -- explore what is in a pack?

hi folks,

I have a git server which gets pushes of data (not code) from a couple hundred VMs every hour. Every round of pushes leaves two stray .keep files, so I am guessing two clients are having problems completing the push. The contents being pushed are reports of a puppet run.

Is there a handy way to list the blobs in a pack, so I can feed them to git-cat-file and see what's in there? I'm sure that'll help me narrow down on the issue.

Are there other ways to try diagnose this?

Does the server-side record anything if a push fails? There are a number of problems I am familiar with, and they always require collaboration from the "client" side to spot and diagnose

 - a ref is not up to date and the server rejects non-ft
 - perms issues over objects or refs
 - ENOSPC
 - ... catchable signals (ETERM?)

AFAIK, I think it doesn't, and maybe it should, even if it's as simple as trying to spawn a pipe to ""/usr/bin/logger -t git-server" and attach it to stderr...

This has veered a bit off topic, but I think it's important for large git server installations.

cheers,

m