Re: Bug#579397: STAT_FAIL to debian for SM_MON of 192.168.120.254, No canonical hostname found for 192.168.120.254

[Chuck Lever <chuck.lever@ORACLE.COM>]

On 05/21/10 09:38 PM, Ben Hutchings wrote:
> On Sat, 2010-05-22 at 07:49 +0800, Steven Shiau wrote:
>> Same problem here. However, mine is on the client side.
>> On sid system, running kernel is 2.6.32-5-686, nfs-common is 1:1.2.2-1.
>> When I mount my NFS server 192.168.120.254, it works. However, if I want
>> to use some tool which need to lock file to save the file on the NFS
>> server, e.g.
>> vgcfgbackup -f $NFS_MNT_POINT/vg.cfg
>> I get the message "lockd: cannot monitor 192.168.120.254", and the
>> message shown on the /var/log/daemon.log:
>> May 21 08:52:44 debian rpc.statd[1298]: STAT_FAIL to debian for SM_MON
>> of 192.168.120.254
>> May 21 08:52:44 debian rpc.statd[1298]: No canonical hostname found for
>> 192.168.120.254
> [...]
>
> nfs-utils 1.2.2 includes the change:
>
> commit 8ce130c4c828b9d13d429f22160f992b9c1d45cd
> Author: Chuck Lever<chuck.lever@oracle.com>
> Date:   Thu Jan 14 12:24:15 2010 -0500
>
>      statd: Support IPv6 in sm_mon_1_svc()
>
> This appears to have removed support for IPv4 literals.  Was this
> intentional?

statd usually requires a DNS reverse mapping for any host it monitors. 
Does your DNS have a reverse mapping for 192.168.120.254?

It looks like the new logic is more restrictive than the old statd when 
mon_name is a presentation address.  The old code simply allowed 
presentation addresses with no reverse mapping.  The new code requires a 
reverse DNS mapping for presentation addresses.  I think even an entry 
in /etc/hosts would allow a raw address to work in this case.

We can probably remove the reverse mapping constraint for presentation 
addresses.  A simple fix might be to change statd_canonical_name() from:

	freeaddrinfo(ai);
	if (!result)
		return NULL;

to

	freeaddrinfo(ai);
	if (!result)
		return strdup(hostname);

Let me know if this works.