How to troubleshoot network slowness

[Sagar Purohit]

Hi

I have 1 server which is working perfectly fine without any issue, but whenever any user uses on remote it is very slow while opening processing and closing so i feel there is some problem in network.

So plese help with what all possible issues can be there on network and hot to troubleshoot

[Leo Laohoo]

I have 1 server which is working perfectly fine without any issue, but whenever any user uses on remote it is very slow while opening processing and closing so i feel there is some problem in network.

1.  Check for speed and duplex issue from the server to the client.

2.  What is the ping time from the computer to the server with, say, large packets?

3.  What is the ping time from the switch port (directly connected to the server) to the server?

[spicert]

If app is fast on LAN, but slow on remote, first define what "remote" means.  VPN, WAN, etc..

MTU is the first thing I check when any IPSec or other encapsulating protocol is in the data path with those symptoms.    MTU issues show up in testing with successful pings (default options), available bandwidth, but when you start an app it's very slow or appears to lock up.      (Web browsing especially shows up as very erratic site response.  Maybe half the page is drawn and then freezes. Or in business apps a simple login page screen appears and then it becomes frozen after logging in.)

You can verify actual MTU by pinging with large packets and df bit set.  

In Cisco routers with VPN  (IPSec, DMVPN, Remote access),  'ip mtu 1400' and 'ip tcp adjust-mss 1360' are good bets, applied on the encapsulating interface.  

(for future searches, I add this late reply.   )

[Tagir Temirgaliyev]

most simple way

from user pc make

ping server_ip -l 100

ping server_ip -l 500

ping server_ip -l 1000

pathping server_ip

and write here results