Taking the Host Subsystem Offline
Before you replace a TXP-CB or a Routing Engine, you must take the host subsystem offline. The host subsystem is taken offline and brought online as a unit. Before you take a host subsystem offline, but sure that you are aware of how this will affect the TX Matrix Plus router and the routing matrix.
To take a host subsystem offline:
- Determine whether the host subsystem is functioning
as the master or as the backup, using one of the two following methods:
- If the green MASTER LED on the Routing Engine is lit, the corresponding host subsystem is functioning as the master.
- Issue the following CLI command. The master Routing Engine
is designated Master in the Current state field:
user@host> show chassis routing-engine sfc 0sfc0-re0: -------------------------------------------------------------------------- Routing Engine status: Slot 0: Current state Master Election priority Master (default) Temperature 27 degrees C / 80 degrees F CPU temperature 42 degrees C / 107 degrees F DRAM 3327 MB Memory utilization 12 percent CPU utilization: User 0 percent Background 0 percent Kernel 2 percent Interrupt 0 percent Idle 98 percent Model RE-TXP-SFC Serial ID 737A-1024 Start time 2009-05-11 17:39:49 PDT Uptime 3 hours, 45 minutes, 25 seconds Last reboot reason Router rebooted after a normal shutdown. Load averages: 1 minute 5 minute 15 minute 0.00 0.00 0.00 Routing Engine status: Slot 1: Current state Backup Election priority Backup (default) Temperature 29 degrees C / 84 degrees F CPU temperature 43 degrees C / 109 degrees F DRAM 3327 MB Memory utilization 11 percent CPU utilization: User 0 percent Background 0 percent Kernel 0 percent Interrupt 0 percent Idle 100 percent Model RE-TXP-SFC Serial ID 737A-1024 Start time 2009-05-11 17:08:54 PDT Uptime 4 hours, 16 minutes, 52 seconds Last reboot reason 0x1:power cycle/failure
- If the host subsystem is functioning as
the master, switch it to backup using the CLI command:
user@host> request chassis routing-engine master switch sfc 0warning: Traffic will be interrupted while the PFE is re-initialized Toggle mastership between Routing Engines ? [yes,no] (no) yes Resolving mastership... Complete. The other Routing Engine becomes the master.
If the Routing Engines are running the same Junos OS Release and are configured for graceful switchover, the standby Routing Engine immediately assumes Routing Engine functions and there is no interruption to packet forwarding. Otherwise, packet forwarding halts while the standby Routing Engine becomes the master and the Packet Forwarding Engine components reset and connect to the new master Routing Engine. For information about configuring graceful switchover, see the Junos High Availability Configuration Guide.
Note: TX Matrix Plus router performance might change if the standby Routing Engine's configuration differs from the former master's configuration. For the most predictable performance, configure the two Routing Engines identically, except for parameters unique to a Routing Engine, such as the hostname defined at the [edit system] hierarchy level and the management interface (em0 or equivalent) defined at the [edit interfaces] hierarchy level.
To configure Routing Engine-specific parameters and still use the same configuration on both Routing Engines, include the appropriate configuration statements under the re0 and re1 statements at the [edit groups] hierarchy level and use the apply-groups statement. For instructions, see the Junos System Basics Configuration Guide.
- To halt the router:
user@host> request system halt sfc 0Halt the system ? [yes,no] (no) yes *** FINAL System shutdown message from user@host *** System going down IMMEDIATELY Terminated ... syncing disks... 11 8 done The operating system has halted. Please press any key to reboot.
Note: The request system halt sfc 0 command halts all Routing Engines on the control plane from which it was issued. To reboot a Routing Engine that has been halted, you must connect through the console. For more information about system commands, see the Junos System Basics and Services Command Reference.
(If two Routing Engines are installed, also issue the command on the backup Routing Engine.) Wait until a message appears on the console confirming that the operating system has halted.
The command shuts down the Routing Engine cleanly, so its state information is preserved. For more information about the command, see the Junos System Basics and Services Command Reference.
Note: The TXP-F13 SIBs might continue forwarding traffic for approximately five minutes after the request system halt command has been issued.
