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<p class=MsoNormal><font size=2 face=Arial><span lang=NO-BOK style='font-size:
10.0pt;font-family:Arial'>Hello!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=NO-BOK style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Over the last couple of days I’ve been trouble
shooting a strange problem with Asterisk.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>First of all, I should say that I’ve been running
Asterisk on a Fedora Core 3 box since last May, but decided to do a
reinstallation of everything due to some problems we’ve had with echos
during conversations (100% SIP based, so no ZAP echos). We are talking about a
low-volume installation running off an Intel Celeron 2.53 GHz box, 512 MB RAM
and some no-name MB (<a
href="https://www.legendmemory.com/modules.php?op=modload&name=News&file=article&sid=412">https://www.legendmemory.com/modules.php?op=modload&name=News&file=article&sid=412</a>).
The internet connection is DSL based, no NAT, eight IP addresses.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The problems continued. I did some tests on the DSL line,
which itself seemed fine. But when I connected Asterisk to the network,
suddenly ping became unstable. We are talking about ping varying between 20 ms
and 600 ms over a connection that usually should result in 20 ms ping. So I
decided to eliminate the chance of increased latency due to traffic, bypassed
the switch and hooked the Asterisk box up directly to the router. I even
disabled Asterisk itself. Still, the problem persisted. It’s worth
mentioning that the latency to the router itself was fine all the time, we’re
just referring to the latency of the Asterisk box.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>So I started installing Linux@home on a spare computer,
about the same specs, only a different motherboard (<a
href="http://www.dealtime.com/xPF-Asrock_MB_PM800_ASROCK_P4VM800_RTL_P4VM800">http://www.dealtime.com/xPF-Asrock_MB_PM800_ASROCK_P4VM800_RTL_P4VM800</a>).
Same issues. At this very moment, I was left with a suspicion that there might
be something with the DSL network, so I contacted the DSL provider and had them
run tests on the line, which all came out just fine. I switched DSL modem/router,
still same problems.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I then decided to do installations of different Linux
distros (no Asterisk installations) on the spare computer, and did some
interesting observings:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>- Debian: Better, only occasional (a few percentage of the
pings performed were above normal, and then only 200 ms above normal, compared
to Centos/Asterisk where 30-40% were above normal). Still not 100%<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>- Mandriva: Perfect latency all the way<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>- Centos (base installation): Problems equal to the ones
described earlier<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I did some further testing, and on a P4 3,0 GHz, 512 MB RAM
and a motherboard which I don’t know the maker /chipet, the CentOS
installation came out with just a small percentage lag in latency.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have checked for IRQ errors, and there seems to be no
conflicts. I do see the network sharing IRQ with the USB bus, but this is
common on motherboards with everything integrated. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I would assume this can be defined as off topic, as it
clearly does not relate to Asterisk in particular. However, I am writing this
in the hope of that someone might have had similar issues before and possibly
been able to solve the problem. Google has not given me much on the subject. It’s
not that I don’t mind putting together a new box with separate and higher
level of quality components, but I’d much rather learn something from this
experience than giving up ;)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Best regards,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Bjorn <o:p></o:p></span></font></p>
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<P><FONT SIZE=2>--<BR>
No virus found in this outgoing message.<BR>
Checked by AVG Free Edition.<BR>
Version: 7.1.385 / Virus Database: 268.3.4/299 - Release Date: 31.03.2006<BR>
</FONT> </P>