Ubuntu
bacula package

bacula-director crashes when nsswitch uses wins for hosts

Bug #590894 reported by Tomasz on 2010-06-07

This bug affects 1 person

Affects		Status	Importance	Assigned to	Milestone
	Bacula	New	Undecided	Unassigned
	bacula (Ubuntu)	Confirmed	Medium	Unassigned

Bug Description

When invoking "status client" for a client Bacula crashes and logs:

Bacula interrupted by signal 11: Segmentation violation

Possible cause is using wins for host name resolution. In Ubuntu 8.04 LTS there were no problems, after upgrade to 10.04 LTS it stopped working.

See original description

Revision history for this message

Tomasz (nowak2000) wrote on 2010-06-07:

nsswitch.conf Edit (481 bytes, text/plain)

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Tomasz (nowak2000) wrote on 2010-06-07:

output from debugging run of bacula director Edit (6.7 KiB, text/plain)

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Tomasz (nowak2000) wrote on 2010-06-07:

manual workaround:
1. ping foo
PING foo (192.168.1.23) 56(84) bytes of data.
64 bytes from foo (192.168.1.23): icmp_seq=1 ttl=128 time=0.263 ms

2. add in /etc/hosts
192.168.1.23 foo

Now bacula works for this client as expected.

Tomasz (nowak2000) on 2010-06-07

description:

updated

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Mathias Gug (mathiaz) wrote on 2010-06-10:

Could you outline which bacula process crashes? Could you outline specific steps to reproduce your issue?

Changed in bacula (Ubuntu):
importance:	Undecided → Medium
status:	New → Incomplete

Revision history for this message

Tomasz (nowak2000) wrote on 2010-06-10:

As the subject says - this bug is about bacula-dir (one of other components crashes also, but I don't remember which one).

Steps:
1. Enable wins hosts resolution, see attached nsswitch.
2. Install on a Windows machine a file daemon, version 2.x.
2. Prepare a job where Client=HOSTNAME-FD, where HOSTNAME-FD is the above mentioned machine - to be resolved with wins.
3. Run the job.

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Tomasz (nowak2000) wrote on 2010-06-27:

debug messages and running under gdb Edit (5.1 KiB, text/plain)

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Tomasz (nowak2000) wrote on 2010-06-27:

Debugging shows problem in bacula-5.0.1/src/lib/bnet.c, function
dlist *bnet_host2ipaddrs(const char *host, int family, const char **errstr)

There are some ifdefs depending on HAVE_IPV6 that may cause this trouble!

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Chuck Short (zulcss) wrote on 2010-08-25:

I have submitted this bug upstream as:

http://bugs.bacula.org/view.php?id=1629

chuck

Changed in bacula (Ubuntu):
status:	Incomplete → Confirmed

Revision history for this message

Kern Sibbald (kern) wrote on 2010-08-25: Re: [Bug 590894] Re: bacula-director crashes when nsswitch uses wins for hosts

On Wednesday 25 August 2010 10:01:27 Chuck Short wrote:
> I have submitted this bug upstream as:
>
> http://bugs.bacula.org/view.php?id=1629
>
> chuck
>
> ** Bug watch added: bugs.bacula.org/ #1629
> http://bugs.bacula.org/view.php?id=1629
>
> ** Changed in: bacula (Ubuntu)
> Status: Incomplete => Confirmed

Thanks -- I have responded to bug report. Bottom line: we need a stack trace
to determine where the problem is occurring, or some step by step
instructions on how to reproduce it (I don't use WINS or even know how to
turn it on).

Kern

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Tomasz (nowak2000) wrote on 2010-08-25:

#10

There is an attachment - see on the right side of the page "Bug attachments" -> "debug messages and running under gdb"
Thanks

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Kern Sibbald (kern) wrote on 2010-08-26: Re: [Bug 590894] Re: bacula-director crashes when nsswitch uses wins for hosts

#11

> There is an attachment - see on the right side of the page "Bug
> attachments" -> "debug messages and running under gdb"

It is just as I suspected: Bacula has called gethostbyname, which then seg
faults when in the wins code. Unless Bacula is passing bad arguments to
gethostbyname, which is highly unlikely, it is not a Bacula bug.

It seems to me that someone has reported this some time ago, so I suspect
it may not be a "Ubuntu" version bug.

Unless someone can show me that Bacula is doing something wrong, I'm
assuming at this point that it as an "upstream" OS or library bug.

Kern