We are seeing random EIO errors when opening files on workstation
clients that, so far, can only be resolved with a reboot of the client.
Environment:
2x replicated IPA servers, Centos 7.5 w/ freeipa 4.5.4-10.el7
NFS server: Centos 7.5
Clients: Mostly Fedora 28, but we've had the same error on Centos 7.5
systems as well. User home accounts are automounted with nfs4+krb5
Scenario:
Upon login, the home directory is always mounted cleanly and
successfully traversed through subdirectories (cd, ls, etc). On an
affected system any attempts to open/read a file will result in
"Input/output error". An strace of the open actually shows the EIO at
the openat syscall:
stat(".bash_profile", {st_mode=S_IFREG|0644, st_size=193, ...}) = 0
openat(AT_FDCWD, ".bash_profile", O_RDONLY) = -1 EIO (Input/output error)
This will then happen for every user that tries to use the workstation.
We've tried restarting every service on the client to attempt to reset
it (ie sssd, gssd, etc) but only a reboot will restore the NFS
functionality. The one other symptom I noticed, is that on an affected
workstation, the klist no longer contains the nfs/ principle for the nfs
server. ie:
Good workstation: gary#> klist -a
Ticket cache: KEYRING:persistent:410400721:krb_ccache_xyvXIky
Default principal: gary@<MYDOMAIN>
Valid starting Expires Service principal
2018-09-18 15:24:44 2018-09-19 15:24:44 nfs/fileserver@<MYDOMAIN>
2018-09-18 15:24:44 2018-09-19 15:24:44 nfs/fileserver@
2018-09-18 15:24:44 2018-09-19 15:24:44 krbtgt/<MYDOMAIN>@<MYDOMAIN>
Bad workstation: gary#> klist
Ticket cache: KEYRING:persistent:410400721:krb_ccache_nY9m2vU
Default principal: gary@<MYDOMAIN>
Valid starting Expires Service principal
2018-09-19 07:25:38 2018-09-20 07:25:38 krbtgt/<MYDOMAIN>@<MYDOMAIN>
Any help, pointers would be appreciated.
Thanks
Gary.
--
Gary Molenkamp Computer Science/Science Technology Services
Systems Administrator University of Western Ontario
molenkam(a)uwo.ca
http://www.csd.uwo.ca
(519) 661-2111 x86882 (519) 661-3566