[Pdns-users] tcp listener issue - hopefully fixed

Thu Sep 9 12:05:59 UTC 2010

On Wed, Sep 08, 2010 at 11:16:41PM +0000, Brad Dameron wrote:
> Bert,
> 
> I canÃ¢ÂÂt seem to get this latest version to run right. I build my RPM. I launch it with the following:

This is not good! Does it crash immediately, even without accepting any
traffic?

So if you bind it to port 54 (for example), does it crash too?

	Bert

> 
> /usr/sbin/pdns_recursor --local-address=172.26.68.42,127.0.0.1
> / --allow-from= --max-cache-entries=3000000 --log-common-errors=no
> / --threads=4 --socket-dir=/var/run/recursor1 --daemon --dont-query=
> 
> pdns_recursor[32283]: Operating in 64 bits mode
> pdns_recursor[32283]: Reading random entropy from '/dev/urandom'
> pdns_recursor[32283]: WARNING: Allowing queries from all IP addresses - this can be a security risk!
> pdns_recursor[32283]: Inserting rfc 1918 private space zones
> pdns_recursor[32283]: Listening for UDP queries on 172.26.68.42:53
> pdns_recursor[32283]: Listening for UDP queries on 127.0.0.1:53
> pdns_recursor[32283]: Enabled TCP data-ready filter for (slight) DoS protection
> pdns_recursor[32283]: Listening for TCP queries on 172.26.68.42:53
> pdns_recursor[32283]: Listening for TCP queries on 127.0.0.1:53
> pdns_recursor[32283]: Calling daemonize, going to background
> pdns_recursor[32284]: Launching 4 threads
> pdns_recursor[32284]: Done priming cache with root hints
> kernel: pdns_recursor[32288] general protection rip:4ea75c rsp:42802840 error:0
> pdns_recursor[32284]: Done priming cache with root hints
> pdns_recursor[32298]: PowerDNS recursor 3.3-pre (C) 2001-2010 PowerDNS.COM BV (Sep  8 2010, 22:53:00, gcc 4.1.2 20080704 (Red Hat
> 
> pdns_recursor[32298]: PowerDNS comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it ac
> the GPL version 2.
> pdns_recursor[32298]: Operating in 64 bits mode
> pdns_recursor[32298]: Reading random entropy from '/dev/urandom'
> pdns_recursor[32298]: WARNING: Allowing queries from all IP addresses - this can be a security risk!
> pdns_recursor[32298]: Inserting rfc 1918 private space zones
> pdns_recursor[32298]: Listening for UDP queries on 172.26.68.42:53
> pdns_recursor[32298]: Listening for UDP queries on 127.0.0.1:53
> pdns_recursor[32298]: Enabled TCP data-ready filter for (slight) DoS protection
> pdns_recursor[32298]: Listening for TCP queries on 172.26.68.42:53
> pdns_recursor[32298]: Listening for TCP queries on 127.0.0.1:53
> pdns_recursor[32298]: Calling daemonize, going to background
> pdns_recursor[32299]: Launching 4 threads
> pdns_recursor[32299]: Done priming cache with root hints
> kernel: pdns_recursor[32300] general protection rip:4ea75c rsp:409ff840 error:0
> pdns_recursor[32307]: PowerDNS recursor 3.3-pre (C) 2001-2010 PowerDNS.COM BV (Sep  8 2010, 22:53:00, gcc 4.1.2 20080704 (Red Hat
> 
> pdns_recursor[32307]: PowerDNS comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it ac
> the GPL version 2.
> pdns_recursor[32307]: Operating in 64 bits mode
> pdns_recursor[32307]: Reading random entropy from '/dev/urandom'
> pdns_recursor[32307]: WARNING: Allowing queries from all IP addresses - this can be a security risk!
> pdns_recursor[32307]: Inserting rfc 1918 private space zones
> pdns_recursor[32307]: Listening for UDP queries on 172.26.68.42:53
> pdns_recursor[32307]: Listening for UDP queries on 127.0.0.1:53
> pdns_recursor[32307]: Enabled TCP data-ready filter for (slight) DoS protection
> pdns_recursor[32307]: Listening for TCP queries on 172.26.68.42:53
> pdns_recursor[32307]: Listening for TCP queries on 127.0.0.1:53
> pdns_recursor[32307]: Calling daemonize, going to background
> pdns_recursor[32308]: Launching 4 threads
> pdns_recursor[32308]: Done priming cache with root hints
> pdns_recursor[32308]: Enabled 'epoll' multiplexer
> kernel: pdns_recursor[32309]: segfault at 0000000000723a41 rip 0000000000723a41 rsp 00000000409ffb18 error 15
> 
> 
> Thanks,
> Brad
> 
> 
> 
> 
> 
> From: pdns-users-bounces at mailman.powerdns.com [mailto:pdns-users-bounces at mailman.powerdns.com] On Behalf Of bert.hubert at netherlabs.nl
> Sent: Tuesday, September 07, 2010 5:45 AM
> To: Mike
> Cc: Brad Dameron; pdns-users at mailman.powerdns.com
> Subject: Re: [Pdns-users] tcp listener issue - hopefully fixed
> 
> Simon,
> 
> Brief reply, am on the road. 3.3 will be released the moment you, brad or laurent confirm the issue is truly gone.
> 
> What I can do is make packages that will be binary identical to the real 3.3 once you 'bless' them as having solved your issue. This would save you an upgrade.
> 
> Would this work for you?
> 
> Bert.
> 
> Sent from my phone.
> 
> ----- Reply message -----
> From: "Simon Bedford" <sbedford at plus.net>
> Date: Mon, Sep 6, 2010 14:16
> Subject: tcp listener issue - hopefully fixed
> To: "bert hubert" <bert.hubert at netherlabs.nl>
> Cc: "Brad Dameron" <Brad.Dameron at clearwire.com>, "pdns-users at mailman.powerdns.com" <pdns-users at mailman.powerdns.com>
> 
> 
> Hi Bert,
> 
> Apologies for the delay in replying I have been assigned to some different work for the moment, I don't think I will get a chance to compile and test this version and was going to wait for the full 3.3 version release.  Do you know how far off this is at all?  Our production systems are still displaying the tcp listener issue but I have a watchdog script restarting it before it maxs out the number of clients so no customer impact, I would be loathed to look at upgrading until we have the full 3.3 deb package if possible.
> 
> Simon
> 
> ________________________________________
> From: bert hubert [bert.hubert at netherlabs.nl]
> Sent: 29 August 2010 15:56
> To: Simon Bedford
> Cc: Brad Dameron; pdns-users at mailman.powerdns.com
> Subject: Re: tcp listener issue - hopefully fixed
> 
> On Mon, Aug 23, 2010 at 11:37:42AM +0100, Simon Bedford wrote:
> > Just returned from annual leave to this welcome news, has anyone had
> > a chance to try it as yet and investigate whether the bug still
> > manifests? And does it no longer happen when running Brad's test
> > script?
> 
> Simon,
> 
> Sadly we found that the previous code drop, while stable, still exhibited
> the same problem.
> 
> We've fixed yet another bug that might be causing the issue, and we are
> currently testing that.
> 
> This drop can be found on
> http://svn.powerdns.com/snapshots/pdns-recursor-3.3-pre.tar.bz2
> 
> If you compile the program below, and run it on your pdns server, you'll
> probably see it print '0' and then a very large number.  If you could share
> that output with us, it could tell us if we are on the right track.
> 
> http://pastie.org/1124088
> http://pastie.org/1124088.txt
> To compile, save as .cpp file and compile with 'g++ -O2 testing.cpp -o testing',
> and run with './testing'.
> 
> Good luck!
> 
>        Bert
> 
> 
> 
> This email may contain confidential and privileged material for the sole use of the intended recipient. Any review, use, distribution or disclosure by others is strictly prohibited. If you are not the intended recipient (or authorized to receive for the recipient), please contact the sender by reply email and delete all copies of this message.