Poor Latency

[jimothy]

I'm after some advice if possible please:

 

I've got a Barracuda Spam Firewall email filter for all our incoming email. The web interface side of this has become slower and slower over the past few months until it's hardly usuable now.

 

I've contacted Barracuda support and they've done a few tests, one of them proved to show a potential issue: the average latency is currently 137 seconds. This seems really high seeing as it's sits on the main core switch on the same vlan as my pc.

 

I've replaced the cat5e patch suspecting it maybe faulty, and the average latency has lowered slighty to 109 seconds, but I thought LAN latency should in the milli-seconds not seconds.

 

I've done some google-ing and can't really see where to start troubleshooting from, anyone got any ideas?

 

Thanks in advance

[pete]

Discounting that barracudas are hateful bits of kit.....

 

1) What's the cpu usage like on your core switch?

2) Is the latency that high only on that port or are others affected?

3) If you plug the barracuda and a laptop into a dumb unmanaged switch (5-port netgear or whatever) is the interface nice and responsive? (after hours test, obviously)

4) Does the barracuda produce dirty traffic? Is the core switch clamping down on what it thinks is dirty traffic?

5) Ask the barracuda support to show you a status report from the box - look for full disks, logs that aren't being rotated and average and peak loads. i.e is the box being swamped and it's slowing down the web interface as a result?

6) If your core switch supports port mirroring, mirror all/some traffic to a spare port. Plug a laptop in running a wireshark capture for an hour or so then review the results.

7) Does the barracuda give status monitoring via snmp or email?

8) If you plug another device (second laptop) into the port the barracuda is using, do you experience similar latency?

 

Smokeping is handy for measuring latency SmokePing - About SmokePing, but Wireshark will give you a better idea what your switch is seeing.

Edited November 11, 2009 by pete

[Fuzzz]

Maybe you already tried is, but have you powercycled the Baracuda?

There could be a memoryleak, so the software is using more and more memory, thus becomming unresponsive due to exessive diskswapping

[jimothy]

@Fuzzz - Thanks for the advice, tried power cycling to no effect.

@pete - Thanks for all the great advice, I'll work my way through all your suggestions and put a post up and let you know what worked, thanks again!

[jimothy]

It's taken a while, and with no bloomin email filtering, I've come to a dead end. I've tried having the barracuda on an isolated network and the performance does seem a little better but still nowhere near usable. I tried different devices in the port the barracuda was attached to, no problem, tried the barracuda in a different port; still poor performance. Switch performance is fine.

 

Barracuda got me to do a firmware reset as there are issue with v4 software on the 200 series box. So we're on v3, but still performance is woeful.

 

@pete: what would you recommend instead of the Barracuda?

[ssiruuk2]

How about using a cloud solution rather than a physical box in your school?

 

We use Webroot to scan our mail for spam / virus before forwarding it onto our exchange server. Avoid Messagelabs if you look into this kind of solution - they are ridiculously priced for a large number of mailboxes.. their idea of an educational discount makes me feel

[mac_shinobi]

not sure if this helps but what about untangle

 

Open Source Network Gateway | Untangle

[somabc]

I'm after some advice if possible please:

 

I've got a Barracuda Spam Firewall email filter for all our incoming email. The web interface side of this has become slower and slower over the past few months until it's hardly usuable now.

 

I've contacted Barracuda support and they've done a few tests, one of them proved to show a potential issue: the average latency is currently 137 seconds. This seems really high seeing as it's sits on the main core switch on the same vlan as my pc.

 

I've replaced the cat5e patch suspecting it maybe faulty, and the average latency has lowered slighty to 109 seconds, but I thought LAN latency should in the milli-seconds not seconds.

 

I've done some google-ing and can't really see where to start troubleshooting from, anyone got any ideas?

 

Thanks in advance

 

Are you sure that is not milliseconds?

[jimothy]

Are you sure that is not milliseconds?

 

yup, sadly it is seconds