https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12988#M392 in ExtremeWare, if the tNetTask is spiked up, that means that there is a lot of traffic going to the CPU of the switch. Look for loops in the network. Thu, 09 Feb 2017 05:43:00 GMT BradP 2017-02-09T05:43:00Z https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12987#M391 Ive found some articles online, nothing of substance however. Only descriptions offered are very vauge like responsible for "switch ethernet traffic". And as a follow up, why would that task suddenly jump on devices from &lt;5% to &gt; 90% then locking up a switch.<BR /> Thu, 09 Feb 2017 05:41:00 GMT https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12987#M391 Jimmy_Sands 2017-02-09T05:41:00Z https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12988#M392 in ExtremeWare, if the tNetTask is spiked up, that means that there is a lot of traffic going to the CPU of the switch. Look for loops in the network. Thu, 09 Feb 2017 05:43:00 GMT https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12988#M392 BradP 2017-02-09T05:43:00Z https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12989#M393 Did, no loops. We even disabled all ports on LAN rtr (the device being bad here) except for the WAN uplink, still did it.....I think, we tried so many things. I know we swapped the device out entirely, same issue. I cant for certain say disabled all ports, a co-worker took over some of the troubleshooting at times. Here an even better one <BR /> <I></I><I></I><I><BR /> tNetTask is the central clearing house for all network I/O. A packet<BR /> </I><I>comes in, netJobAdd'ed, and tNetTask does everything for the packet for its lifetime. This is done for all packets, all network interfaces, </I><I>and the entire TCP/IP stack.<BR /> <BR /> </I>Packet captures are showing nothing of substance. Thu, 09 Feb 2017 10:11:00 GMT https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12989#M393 Jimmy_Sands 2017-02-09T10:11:00Z https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12990#M394 Hi Jimmy,<BR /> <BR /> did you take packet captures on the WAN uplink port and look for potentially problematic traffic? E.g. IP packets with IP options set, or a TTL of 1, or UDP data sent to an IP without ARP entry? Anything that would be forwarded in software?<BR /> <BR /> Switches are not designed for software forwarding, thus "normal" amounts of traffic needing software forwarding might be sufficient to overload the CPU.<BR /> <BR /> Erik Thu, 09 Feb 2017 10:11:00 GMT https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12990#M394 Erik_Auerswald 2017-02-09T10:11:00Z https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12991#M395 Run the command "top" a few times and check the highest processes Thu, 09 Feb 2017 14:24:00 GMT https://community.extremenetworks.com/t5/network-architecture-design/what-is-the-task-tnettask-resonsible-for/m-p/12991#M395 Jason_Parker 2017-02-09T14:24:00Z