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Hello,

I'm trying to troubleshoot an issue on my network where webpages are loading slowly over our network cards. Internet works just fine over wireless (sonicpoints connected to the sonicwall firewall). All my switches and firewalls are up to date and there are no errors or faults on any of them. This slowness is happening with every computer in the office.

Our provider, Century Link, is running with no problem. Streaming and downloading is as fast as it usually is and speedtests show up to 45mbps free out of a 50mb internet connection.

I started running wireshark scans and I don't see a lot of broadcasts at all. I do however see a lot of tcp retransmissions and "previous segment not captured" when I run a capture on port 80 over the network card (with wireless disabled). Captures on the wireless show almost no TCP retransmissions at all.

Thoughts? How can I upload a capture?

asked 05 Jan '15, 10:17

RCFAdmin's gravatar image

RCFAdmin
11112
accept rate: 0%

take a capture during issue and you can upload it to cloudshark.

(05 Jan '15, 21:16) kishan pandey

I do however see a lot of tcp retransmissions ... when I run a capture .... over the network card (with wireless disabled).
Captures on the wireless show almost no TCP retransmissions at all.

Sounds like a problem with your LAN infrastrcuture. Some ideas:

  • The LAN interface of your SonicWall might be "broken". Please check the error counters for that interface. Your local SonicWall guru should know how to do that.
  • The Switch interface, where your SonicWall is connected to, might be broken. Please check the error counters for that interface on the switch. Your local switch guru should know how to do that.
  • One of the network switches could be overloaded. Maybe high CPU load due to a loop on that switch. Your local switch guru should know how to check that.
  • Check/Replace the network cables to/from the SonicWall to the switch
  • There might be a QoS policy configured on the SonicWall that applies only to traffic from the LAN and not from the Wireless network. Please check that as well.

Regards
Kurt

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answered 07 Jan '15, 01:56

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%

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question asked: 05 Jan '15, 10:17

question was seen: 2,610 times

last updated: 07 Jan '15, 01:56

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