Packets are dropped through the PacketShaper

Products

• PacketShaper

Issue/Introduction

Packets are being dropped when passing through the PacketShaper.

Resolution

There may be various reasons for the packet drops. 

Please verify the following: 

1. The speed and duplex settings are set to same value on the PacketShaper interfaces and the interfaces on the directly connected devices. 
2. Change the interface setting from manual to auto, or if it was auto, then change it to manual, on both PacketShaper and the directly connected devices. 
3. If you still see the drops through the PacketShaper, change the network cable on the PacketShaper. (Check the NIC statistics and make sure there are no CRC/Frame/etc. errors).
4. In some cases, the drops could also be due to performance issues or drops could be in Software code rather than Hardware. You can try 'setup shaping passthru'. In this mode, PacketShaper's NIC is still active but it will stop all PacketShaper functionalities (no shaping, no classification, no reporting). If you still see drops then it could be HW issue (see step 5) OR if you no longer see drops then it could be PacketShaper performance issue. You may want to troubleshoot performance issues with setup shaping OFF and setup shaping ON. Check the output of: sys health; link show; partition show; etc. You can try 'setup shaping off' - if this helps then either the box is overloaded due to shaping or shaping Policies and Partitions are causing the slowness. Try to check Policies and Partitions are not too restrictive. Check CPU usage with shaping ON vs OFF. If you have too many Rate Policies, Partitions, Dynamic Partitions, then it could add to the CPU load.
5. However, if you still see the drops through the PacketShaper even with 'setup shaping passthru', set shaping to bypass mode - 'setup shaping bypass' (see Note below). With this mode, all traffic will traverse through the built-in bypass relays. It is as if you have wired around the PacketShaper OR at this point PacketShaper as a piece of wire. If you do not see any drops in this step, then the PacketShaper NIC interface has probably become faulty. If you still see packet drops when the PacketShaper in in the bypass mode then the problem is not on PacketShaper, it could be in the cable, it could be in the devices connected to the PacketShaper or somewhere else.

Note: Make sure that you are connected to the PacketShaper through the console before setting shaping to bypass mode, because when the PacketShaper is in bypass mode, you will be able to access it only through the console (you will not be able to communicate via NIC ports). After testing, you may revert shaping to off or on based on your configuration.