Packet loss in switch

[wfqk]

Hi Please see the attached picture, which comes from Solarwind. The orange represents packets loss. Switch is 2960. some packets were lost. What kind of reason can cause the issue? Thank you!

[balaji.bandi]

We can not rely on 100% with Solarwinds here. because you may have lost connection between Device and Solarwinds poller.

is this issue with only this device ?  what do you see on the Device Logs ?

[Reza Sharifi]

Hi,

Is this for the whole switch? In the main Orion summary page, you can simply hover your mouse over the device and SW will show you CPU usage, packet loss, memory usage, and bunch other stuff. Also, by default, Orion shows packet loss in red. So, are you looking at the correct device and parameters?

HTH

[wfqk]

In another picture in solarwind, it shows red(please see attached one). As it shows packet loss, why it did not show which interface cause the issue? can we know which interface lost the packet? In show log of the switch, i didnt see error which can be related to the packet loss. 

[Reza Sharifi]

Ok, much better picture. So, this shows that the switch lost connectivity between 7 and 7:15 am. Now it is not clear if the switch was down for all the entire 15 minutes or for example for 12 min, 13 min, etc.. If you want to get deeper, you can drag your mouse on that 15 min window and it will give you a more exact time frame. Also, It appears that this was not an issue with a particular interface and rather with the whole switch losing connection to Orion. Did the switch reboot during this time? "sh ver" should show you the uptime. Also, you can always set alerts, so when an interface or a whole switch goes down you get an alert via email and/or text.

HTH

[balaji.bandi]

ok we can see solarwind point of view.

can you post show version from switch. what is the logs in the switch that time ?

what is the IP address of the Switch and Solarwind server IP

how many devices in the path ?

[wfqk]

Thank you for your explaining. I did show ver, and it does not show whole switch shutdown. and i can see the log show some interface down for short while. not sure if it is related with this. Probably it is connection issue with Orion. but we often have this kind issue in several switch devices. Once in a while we got alert like this. 

Another question is, since the interface lost packets, can we know which interface cause the issue? Can we get the answer directly from Orion? 

[Reza Sharifi · Accepted solution]

If the switch did not go down, that means the interface connecting in the path of Orion has lost connectivity to the switch. You can look at the switch interfaces and see what interface has gone down at that specific time. 

In addition to looking at the switch connectivity, you may also want to look at the Orion backend server for logs in case of any issues there. 

HTH

[Reza Sharifi]

If this is production and the switch being up and running 24x7, 7 days a week is important, I recommend you set up some alerts proactively, so next time this happens, you will receive an email notification and/or text on your cell. 

Good Luck!

[wfqk]

As the interface connecting in the path of Orion has lost connectivity to the switch, why it did not say losing 100% packets at that period time? i guess it is because of sampling time issue. 

[balaji.bandi · Accepted solution]

yes this most seen issue while solarwind lost connection, and by the time next poll it will be back online, this period solarwinds thinks device not lost. change the polling time to less also have high CPU some times.

[Reza Sharifi]

The polling interval for SW is every 2 minutes. I don't recommend you change that before calling and consulting with SW tech support.

HTH

[wfqk]

Thank you very much!!