Similar symptoms (uid/gid 4294967294) can also be caused by running
against the root's keyring quota in the kernel, which is used to store
all the id_resolv/id_legacy keys for each uid and gid.
The default kernel keyring quotas (200 keys!) in jessie's 3.16 kernel
work poorly for NFSv4 setups with more than ~100 users. The
kernel.keys.root_{maxkeys,maxbytes} sysctls should be bumped higher:
$ sudo sysctl kernel.keys.root_maxbytes=25000000
kernel.keys.root_maxkeys=1000000
Using the new Linux 3.18 default values:
>
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=738c5d190f6540539a04baf36ce21d46b5da04bd
Works much better with all of the 4294967294 UIDs now showing correctly.
$ sudo head -n1 /proc/key-users
0: 1248 1247/1247 1243/1000000 31475/25000000
With the current kernel.keys.root_maxkeys=200 default in 3.16, this will
quickly be saturated.
Relevant Ubuntu bug:
https://bugs.launchpad.net/fedora/+bug/1124250
-- Tero Marttila
