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New Member

How to troubleshoot slow network

Hi there,

I am a network admin and am experiencing slow network connection across all VLANs in my LAN. Any ideas on isolating and troubleshooting my problem? Thanks a lot.


Re: How to troubleshoot slow network


Well there are lots of points to be considered and checked out in the process of troubleshooting the LAN.

It all starts with the kinda topology u have in place and also the traffic flow in ur network,switch models.

If you on theoritical basis its 80-20 in which 80% of the whole traffic will be staying in ur local network(LAN) and just 20% is gonna traverse out from ur network.

Also u can check up for normal collisions ,errors or other variants of them like giants,runts in ur switch ports.

Before getting onto something inline would also suggest to check up for the Antivirus status and the reqd patches for the systems..

Also you can enabled something like ip cache flow in ur router if u have one in place out there to chck the traffic patterns and the source/destination hosts involved in those transactions..


New Member

Re: How to troubleshoot slow network

There's no way anyone can troubleshoot without information but some general questions you'll want to answer...

* Is the problem occuring for devices within a VLAN or only between devices on different VLANs?

* Are there errors on trunks and router links between various VLANS? Something as simple as a duplex mis-match on a link can cause some very severe issues.

* Is it really a general problem or does it just look that way because two or three boxes are having problems communicating? Compile a list of affected servers and hosts and pay attention to where they all connect to the network.

Troubleshooting is about asking questions that help you narrow down the possible causes of the problem. A "slow connection across all VLANs" is two broad to really do much with.