Troubleshooting Policy Engine Issues


This chapter describes how to identify and resolve problems that might occur on the policy engine.

This chapter includes the following sections:

Policy Engine Troubleshooting Commands

Policy/Rule Not Working as Expected

Policy/Rule Based on VM Attributes Not Working - But Without VM Attributes Policy/Rule Works

Policy/Rule Configured for Non-firewalled VMs (port-profiles) Not Working

Policy Engine Statistics Show Hits as 0 and Traffic Not Reaching the Cisco VSG

Policy Engine Troubleshooting Commands

When there are policy engine issues, use these commands to troubleshoot:

show run ruleDisplays all rules configured in the Cisco VSG

show run policyDisplays all policies configured in the Cisco VSG

show run zoneDisplays all zones configured in the Cisco VSG

show run object-groupDisplays all object-groups configured in the Cisco VSG

show policy-engine statsDisplays statistics about the rule hits in the Cisco VSG

clear policy-engine statsClears the statistics about the rule hits in the Cisco VSG

Policy/Rule Not Working as Expected

When policies or rules do not work as expected, do the following:

Check the show policy-engine statistics and verify that the hits are incrementing by entering the show policy-engine stats command. If not, go to the module interactions section to see why hits are not incrementing.

When policy engine statistics are incrementing, check the rule name that is being hit.

View the configuration of the rule by entering the show run rule rule-name command. Verify that the conditions are configured correctly.

Policy/Rule Based on VM Attributes Not Working - But Without VM Attributes Policy/Rule Works

A policy or rule with VM attributes requires additional data for the Cisco VSG to evaluate the policy engine. This data, if not complete, can result into incorrect or not applicable hits in the statistics. When the policy or rule is configured with VM attributes, make sure that you see VM information in the following outputs:

show vsg ip-bindingThe output should have the IPs of all the VMs for which the rules will be written in the Cisco VSG.

show vsg dvport—The output should have port profile and IP information of all the VMs for which rules will be written in the Cisco VSG.

show vsg vm—The output should have VM attribute values (whichever present in the vCenter for a given VM) of all the VMs for which rules will be written in the Cisco VSG.

Policy/Rule Configured for Non-firewalled VMs (port-profiles) Not Working

Typically, to enable firewall protection for a VM, you need to configure the vn-service and org CLI in the port profile at the VSM. Learning of IP addresses and other attributes for the VM is enabled with firewall protection.

To write policies or rules for VMs based on the vCenter attributes (and at the same time not be protected), configure the org CLI only in the port profile to enable learning of IP addresses and other attributes for the VM but no firewall protection (for example, a client VM running Windows OS and a server running the Linux OS). To turn on firewall protection for the server VM (any traffic to or from server VM is protected by the Cisco VSG but not the client VM), write a rule saying the source with the Windows OS and destination with the Linux OS VM is permitted. To achieve this, do the following:

Configure the vn-service and org CLI in the server VM port profile at the VSM.

Configure the org CLI for the client VM port profile at VSM (no vn-service).

Write a rule with a source condition OS name that contains the Windows and a destination VM name server VM, action permit.

Policy Engine Statistics Show Hits as 0 and Traffic Not Reaching the Cisco VSG

Verify if the correct MAC address is displayed by entering the show vsn brief in the VSM. The MAC address should be the MAC address of the Cisco VSG data interface. If the MAC address is correct, check the following:

Confirm that the buffers in use are not zero by entering the show ac-driver statistics command. If zero, then check/fix the adapter type.

The Cisco VSG data0 interface's adapter type in the VSM VM properties should be set to VMXNET3.

If the Cisco VSG data interface adapter type E1000 does not work properly, set to VMXNET3.

When the Cisco VSG is deployed using the OVA format, it does not have this issue because the adapter type is automatically correctly selected.