Configuring Junos OS to Upgrade and Downgrade Switch Interface Boards on a TX Matrix Router
The Junos OS does not support mixed mode operation of Switch Interface Boards (SIBs). To successfully upgrade 1.0 SIBs to 2.0 SIBs in a TX Matrix environment, you must force all newly installed 2.0 SIBs to operate in 1.0 mode until the upgrade is complete.
Configuring Junos OS to Upgrade Switch Interface Boards on a TX Matrix Router
To configure the TX Matrix router to support a SIB upgrade, include the fabric upgrade-mode statement at the [edit chassis] hierarchy level and commit the changes to update the configuration. Configuration changes that you commit on the TX Matrix router are propagated to all T640 routers in a routing matrix.
The fabric upgrade-mode statement instructs the newly installed 2.0 boards to operate in 1.0 mode. When all 1.0 boards have been replaced by 2.0 boards, remove the fabric upgrade-mode statement from the configuration hierarchy, and commit the changes again.
In the TX Matrix routing environment, use the request chassis sib (offline | online) command sequence to power cycle the newly installed 2.0 SIBs. Power cycling is not needed in a single chassis T640 environment.
As the system discovers each new board, the 2.0 ASIC enables 2.0 features, and the upgrade is complete.
Configuring Junos OS to Downgrade Switch Interface Boards on a TX Matrix Router
To downgrade your 2.0 SIBs to 1.0 SIBs, follow the upgrade procedure. When you replace the first 2.0 SIB with a 1.0 SIB, the system operates in a downgraded 1.0 mode until all 2.0 SIBs are replaced, and the newly installed 1.0 SIBs are power cycled using a request chassis sib (offline | online) command sequence.
The TX Matrix switch fabric supports 2.0 SIBs for enabling Gigabit FPC-4 and Type 4 PICs. Gigabit FPC-4 devices are not compatible with 1.0 SIBs. Therefore, if you are planning to downgrade from 2.0 SIBs to 1.0 SIBs, you must take all Gigabit FPC-4 devices offline to ensure that the link between the new SIBs and the FPC does not fail.