RE: [PHP-DB] Mysterious 5 second delay on sybase_connect()

nsswitch seems to be OK, but it wasn't aliased to localhost for ipv6. I've fixed that now (and knocked back the ipv6 precedence in /etc/gai.conf) and it seems to be behaving... Still doesn't explain to me why it was looking itself up in the first place... Weird :/ -- Tom -----Original Message----- From: charlesmorris@gmail.com [mailto:charlesmorris@gmail.com] On Behalf Of Charles Morris Sent: 24 May 2012 17:40 To: Tom Lloyd Cc: Matijn Woudt; php-db@lists.php.net Subject: Re: [PHP-DB] Mysterious 5 second delay on sybase_connect() Is it's own host name in the hosts file and nsswitch.conf set up correctly? Alternatively disable all the ipv6 adapters if you aren't using them. On Thu, May 24, 2012 at 12:23 PM, Tom Lloyd <TomLloyd@wallcolmonoy.co.uk> wrote: > Say the webserver is called foo, on the domain company.local.  No ipv6 is enabled in the > network.  A network trace tells me that when the HTTP request comes in, the webserver sends out a > DNS request for "AAAA foo.company.local".  Nothing replies, and after 5 seconds it times > out and carries on doing what it was doing. > > Why would it be doing a DNS lookup for the IPv6 address of its own hostname?  And more > urgently, how can I stop it? > > -----Original Message----- > From: Tom Lloyd > Sent: 24 May 2012 16:26 > To: 'Matijn Woudt' > Cc: php-db@lists.php.net > Subject: RE: [PHP-DB] Mysterious 5 second delay on sybase_connect() > > I'm getting increasingly suspicious that DNS is to blame.  If I was to do something like: > > $conn = sybase_connect( "10.0.0.11\SQLMAIN", $user, $pass ) > > Would that trigger a lookup of some variety? > > -----Original Message----- > From: Matijn Woudt [mailto:tijnema@gmail.com] > Sent: 24 May 2012 13:00 > To: Tom Lloyd > Cc: php-db@lists.php.net > Subject: Re: [PHP-DB] Mysterious 5 second delay on sybase_connect() > > On Thu, May 24, 2012 at 10:51 AM, Tom Lloyd <TomLloyd@wallcolmonoy.co.uk> wrote: >> Hi there.  I'm working on a PHP-driven project on Debian Squeeze that >> connects to an instance of Microsoft SQL Server on Windows Server 2008. >> I'm using the sybase extensions to PHP. >> >> Since I rebooted the webserver on the weekend, both the >> sybase_connect() and sybase_pconnect() commands will sometimes take >> exactly 5 seconds to execute.  It seems to be random whether they do >> this or not.  I can't think of anything that could have been changed >> by the reboot, unless a package was updated but its associated process never got >> restarted... >> >> Does anyone know what might cause this behaviour? >> >> Cheers, >> Tom Lloyd >> > > It most likely has nothing to do with PHP, but is rather a routing issue. 5 seconds is the > default connection time out for TCP/IP, so it probably makes sense that the connection is failing at > a lower level. > > - Matijn