Bug 1192806

(In reply to Jean-Jacques Sarton from comment #0)
> Description of problem:
> I have 2 system with FC21, one new PC and an older notebook
> both system exports NFS4 resources and can mount the exports
> from the other system.
> 
> On the notebook, mounting the exported directories from the PC
> fail:
> Feb 15 13:56:01 nb rpc.gssd[948]: ERROR: unable to resolve 2001:db8:1::4
> ...wn
> Feb 15 13:56:01 nb rpc.gssd[948]: ERROR: failed to read service info
> Feb 15 13:56:01 nb rpc.gssd[948]: ERROR: unable to resolve 192.168.1.4
> to...wn
> Feb 15 13:56:01 nb rpc.gssd[948]: ERROR: failed to read service info
> 
This looks like a DNS issued... Why can't those address be resolved?

DNS work as expected. At mount time the names are resolved as required (Call to host pc). If I insert the pc addresses to the /etc/hosts file the problem remain.

If I look ate the time where the daemon are started on both systems, there are no differences which can explain the problem.

The configuration of both pc and notebook are practically identical.

If the /etc/fstab file contain the IP Address for the server the same problem occur so that the problem can't be DNS.

(In reply to Jean-Jacques Sarton from comment #3)
> If the /etc/fstab file contain the IP Address for the server the same
> problem occur so that the problem can't be DNS.

Here is the code that is failing 

    err = getnameinfo(sa, addrlen, hbuf, sizeof(hbuf), NULL, 0,
              NI_NAMEREQD);
    if (err) {
        printerr(0, "ERROR: unable to resolve %s to hostname: %s\n",
             addr, err == EAI_SYSTEM ? strerror(errno) :
                           gai_strerror(err));
        return NULL;
    }
What is the entire error message? I'm looking for string that
either gai_strerror() or strerror() logged.

Sorry for the delay, the system nb what defekt so I had to buy a new system and to install the old software ti the new one.

The message are:

rpc.gssd[###]: ERROR: unable to resolve 2001:db8:1::4 to hostname: Name or service not known
rpc.gssd[###]: ERROR: failed to read service info

(In reply to Jean-Jacques Sarton from comment #5)
> Sorry for the delay, the system nb what defekt so I had to buy a new system
> and to install the old software ti the new one.
> 
> The message are:
> 
> rpc.gssd[###]: ERROR: unable to resolve 2001:db8:1::4 to hostname: Name or
> service not known
> rpc.gssd[###]: ERROR: failed to read service info
Does the ipv4 address for 2001:db8:1::4 work?

for IPv4 this exactly the same.

This result to the same problem. For Ipv4 there are no behaviour changes.

This message is a reminder that Fedora 21 is nearing its end of life.
Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 21. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
this bug will be closed as EOL if it remains open with a Fedora  'version'
of '21'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 21 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Fedora 21 changed to end-of-life (EOL) status on 2015-12-01. Fedora 21 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.

FYI: I just ran into this bug on my freshly upgraded CentOS 7.3 machine.

The bug seems to be triggered when rpc.gssd is started before the network is fully configured.

I did an strace on the failing rpc.gssd process while trying to do a mount, and it first looks at /etc/hosts and then it tries to query a (non-existant) DNS server at 127.0.0.1(?). 

Note that at this point the network, DNS and all other processes were working fine. But the rpc.gssd process seems to be stuck in some weird (glibc?) host lookup fallback scenario were it doesn't look at /etc/resolv.conf anymore.

After a restart of rpc.gssd everything works and I can see it looking at /etc/resolv.conf and querying the specified DNS servers.

As a workaround I've now delayed the start of rpc.gssd.service until after the network-online.target is reached.

(In reply to Robbert Eggermont from comment #11)
> FYI: I just ran into this bug on my freshly upgraded CentOS 7.3 machine.

Hitting it on CentOS 7.2 here as well. I'm trying to avoid a reboot, but restarting "gssproxy auth-rpcgss-module rpc-gssd rpc-svcgssd" didn't fix it.

(In reply to RevRagnarok from comment #12)
> (In reply to Robbert Eggermont from comment #11)
> > FYI: I just ran into this bug on my freshly upgraded CentOS 7.3 machine.
> 
> Hitting it on CentOS 7.2 here as well. I'm trying to avoid a reboot, but
> restarting "gssproxy auth-rpcgss-module rpc-gssd rpc-svcgssd" didn't fix it.

I was incorrect; this was not my problem. The rpc.gssd was a red herring. Our problem was that the exports file on the server was incorrectly formatted.