The txqueuelen parameter of an interface in the Linux kernel. It limits the number of packets in the transmission queue in the interface's device driver.
The default value of txqueuelen is 1000 for Veeam PN appliance server deployed from Azure Marketplace or from OVA template. Values of up to 8000 have been used successfully to further improve performance. If a host is low performance or has slow links, having too big txqueuelen may disturb interactive performance.
To change the value of txqueuelen, log in to the Veeam PN appliance TTY console and run the following command:
ifconfig ens160 txqueuelen 4000