Alcatel Carrier Internetworking Solutions 6648 - Manual (Page 154)

Troubleshooting QoS Troubleshooting QoS
page 10-4 OmniSwitch Troubleshooting Guide September 2005
QoS Apply
Another common mistake for having a policy not work is to forget to apply the QoS configuration to the
configuration. Most QoS commands require a qos apply CLI command before the configuration is active.
This is valid for QoS configuration on the CLI. Loading a QoS ASCII configuration file does not require a
qos apply command.
Note. Use the qos apply CLI command to activate your QoS settings. (You still need to save on exit.)
Rebooting without applying the changes will cause the settings to return to their last applied values.
Invalid Policies
Valid condition/action combinations are listed in the user manual. The CLI prevents you from configuring
invalid condition combinations that are never allowed.
Use the Policy Condition/Action Combinations table in the user documentation as a guide when creating
policy rules.
Two important limitations to remember:
• Layer 2 and Layer 3/4 conditions should not be combined.
• Layer 2 conditions cannot combine source and destination parameters.
• On the OmniSwitch 6624/6648, source and destination parameters may not be combined in the same
condition.
Rules Order
The order of entry when defining rules use policy rule command with the precedence option. The Range
for precedence is 0-65535. The rule with the highest precedence will be applied.
When a flow comes into the switch, the Layer 2 source rules are examined first for a match. If no match is
found, the Layer 2 destination rules are examined. If no match is found, the Layer 3 rules are examined. If
a flow matches more than one rule in a particular precedence list (for example, the Layer 2 source list), the
precedence determines which rule the switch will apply to the flow.
More than one rule may have the same condition, but the rule with the highest precedence will be applied
to the flow matching the condition. If a policy is configured with the same precedence value as another
policy, the policy that was created first has the higher precedence. The new policy is considered lower
priority.
For the following rules, if condition “oktftp” and “noip” are satisfied, the rule “oktftp” would take prece-
dence over rule “nopip” because it has a higher precedence number. See the examples below:
-> policy rule oktftp precedence 200 condition oktftp action oktftp
-> policy rule noip precedence 100 condition noip action noip