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Packet Sniffer frequently reports 0 bits/s




I have a remote probe installed on a Windows 10 VM on a proxmox virtual host, which has a 10 gigabit physical link of the host machine bridged to it. The physical link in turn is connected to a SPAN port on my core switch. In PRTG I have a Packet Sniffer Sensor configured on the remote probe which monitors the specified interface. As frequently as every minute, the graph drops to 0 bits/s and picks back up at the next interval, while Windows reports steady incoming traffic. Also, the reported traffic sum (when its not 0) is always a good amount lower than what the Switch is reporting is going out of its SPAN Port to the host, for example the switch interface reports 1gbit outgoing, at the same time the Packet Sniffer only reports 350mbit. I already checked MTU size of the switch, vm settings in the hypervisor and windows setting inside the vm. CPU and RAM ressources are plenty available. Drivers are up to date and interface settings such as speed and duplex are configured/match.
One thing i noticed is, when the VM is being rebooted, for about 4-5 minutes everything looks fine, then the reported traffic drops dramatically in Packet Sniffer Sensor and a short while after that the drops to 0bits/s start occuring again.
It almost feels as if some sort of buffer or queue starts to build up and can´t be emptied fast enough, but I don´t know where else to check for a problem like that. Maybe you can point me in the right direction or give some other clues that could help alleviate the problem. Any help is much appreciated.

packet-sniffer prtg remote-probe

Created on Jan 13, 2023 1:38:38 PM

Last change on Jan 16, 2023 8:49:30 AM by  Felix Wiesneth [Paessler Support]

2 Replies



We would like to look deeper into this issue and for that we need specific information from your PRTG instance. Please forward us a Support Bundle including the system log files for analysis. This can be done via the "Contact Support" ribbon in the lower right corner of the web interface. This will give us plenty of information so we can analyze the overall health of the server and other settings so we can do some research if we notice something odd.

Created on Jan 18, 2023 4:48:28 AM by  Jonathan Mena [Paessler Technical Support]



Hi Jonathan,

thanks for your reply. I have just forwarded the requested information.

Created on Jan 19, 2023 9:25:55 AM

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