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Slow network speed

Hey guys,

I have 2 sonicwall firewalls setup as HA. I also have 2 WAN connections (1 fiber, 1 coax) and i connected a Cisco SG300 from both ISP handoff's but my speed was really slow.

Do i need a more powerful switch?
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Benjamin MOREAUProject Manager

Commented:
Check your "MTU" settings on your WAN (of your Sonicwall). Maybe you have to reduce MTU (check with your ISP)

Author

Commented:
Why would that matter, the sonicwall was working fine before I added the switch in front of it.
Project Manager
Commented:
Sorry, i have understand that it was a new install...

Maybe you have pb with "auto negociation" between switch & sonicwall. Try to force speed on firewall & cisco.

Author

Commented:
Ok i can try that, is that switch powerful enough to handle a 100MB and a 20MB wan connections?
Benjamin MOREAUProject Manager

Commented:
I think yes because the smallest Cisco SG300 (SG300-08) acapcity is 1,6GBits/s...

http://www.cisco.com/c/en/us/products/collateral/switches/small-business-smart-switches/data_sheet_c78-610061.html


I think you also have to check MTU on your Switch... depending of your switch config; you can have a least MTU than on your firewall & ISP.
Kamran ArshadIT Associate

Commented:
Hi,

Is it slow speed for every device or just a few machines? You can check the total bandwidth available using IPerf. It will also let you know the latency and jitters.

http://openmaniak.com/iperf.php

Btw the Internet is terminated at UTM and switch is installed after that right?

Author

Commented:
Yes slow for everyone.

Your right, terminated at utm and switch is after.
Kamran ArshadIT Associate

Commented:
Can you connect a laptop to the  utm directly bypassing the switch and check the speed? This will confirm issue with switch. ..I suspect it is not issue with switch but off course I can be wrong :)

Author

Commented:
without the switch, it was running fine!