On a SL 7.3 + updates, and a 7.4 machine I was seeing trouble mounting
sec=krb5 nfs mounts.  audit.log had a lot of:

type=AVC msg=audit(1504198638.609:3046): avc:  denied  { read } for  pid=17510
comm="rpc.gssd" scontext=system_u:system_r:gssd_t:s0
tcontext=system_u:system_r:unconfined_service_t:s0 tclass=key
type=AVC msg=audit(1504198638.609:3047): avc:  denied  { write } for
pid=17510 comm="rpc.gssd" scontext=system_u:system_r:gssd_t:s0
tcontext=system_u:system_r:unconfined_service_t:s0 tclass=key

Ran audit2allow to create a local policy and that got mounts working again.
Although I think I've seen these on machines without ill effects as well, but
not sure.

I've filed https://bugzilla.redhat.com/show_bug.cgi?id=1487350

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Orion Poplawski
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