Latency Pinging LAN Switch
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05-22-2008 03:45 AM - edited 03-05-2019 11:09 PM
I have 3*3750s Stacked switches in my LAN. When I ping other devices on the LAN, the ping time is < or = 1ms. However when I ping the switch itself, the ping time can go up to 25 ms. Please advice on what is happening.
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05-22-2008 03:54 AM
use "pathping" AND TRACERT command check where packet is droping ..
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05-22-2008 09:37 PM
Whe I do a Tracert, it shows that the switch is reached instantly and dirrectly.
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05-22-2008 05:27 AM
Ping response from a switch interface is put on low priority and is not a good way to test latency , always ping to a device hung off the switch itself .

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05-22-2008 08:51 AM
Agreed, ICMP is a low priority process. Maybe you have something else going on on this switch?
Check:
sh proc cpu
sh int | inc is up|drop
You may have the CPU chewing on some packets hitting the SW queues. See if you have drops or flushes in the software queues (L3 interfaces).
Regards,
John Gill
