Alcatel-Lucent 7210 SAS M Interface Configuration Manual page 174

• It is not recommend to change the service parameters for the SAP and the service when loopback is
active. Additionally use of commands which clears the FDB, and so on is highly discouraged.
• Remove the loopback on the SAP port to bring the sap out of MAC swap with loopback mode.
The no form of the command disables physical layer loopback on the Ethernet port.
Note: The loop back command is not saved in the configuration file across a reboot.
Listed below is the recommended sequence of commands to be executed to perform loop back:
1. Disable the port, execute the command config>port> shutdown.
2. Enable loop back, execute the command config >port>ethernet> loopback internal
3. Enable the port, execute the command config>port> no shutdown.
4. Perform the required tests.
5. Disable the port, execute the command config>port> shutdown.
6. Disable loop back, execute the command config >port>ethernet> no loopback internal
7. Enable the port, execute the command config>port> no shutdown.
8. Enable the required services.
Listed below is the recommended sequence of commands to be executed to perform loop back when SFP or
XFPs are inserted into the device :
1. Insert SFP or XFPs. SFP or XFPs are not required in case of fixed copper ports.
2. Enable the port and execute the command config>port> [no] shutdown.
3. Disable the port and execute the command config>port> shutdown.
4. Enable loop back and execute the command config >port>ethernet> loopback internal
5. Enable the port and execute the command config>port> no shutdown.
6. Perform the required tests.
7. Disable the port and execute the command config>port> shutdown.
8. Disable loop back and execute the command config >port>ethernet> no loopback internal
9. Enable the port and execute the command config>port> no shutdown.
10. Enable the required services.
Listed below is the sequence of commands to be executed to perform loop back when SFP or XFPs are
changed :
1. Disable the port, execute the command config>port> shutdown.
2. Insert the new SFP or XFP.
3. Enable the port and execute the command config>port> no shutdown.
4. Disable the port and execute the command config>port> shutdown.
5. Enable loop back and execute the command config >port>ethernet> loopback internal.
6. Enable the port and execute the command config>port> no shutdown.
7. Perform the required tests.
8. Disable the port and execute the command config>port> shutdown.
7210 SAS M, T, X, R6, R12, Mxp Interface Configuration Guide
Interface Configuration
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