- request system snapshot
- <as-primary>
- <config-size size>
- <data-size size>
- <factory>
- <media type >
- <partition>
- <root-size size>
- <swap-size size>
Command introduced before JUNOS Release 7.4.
Back up the currently running and active file system partitions on the router to standby partitions that are not running. Specifically, the root file system (/) is backed up to /altroot, and /config is backed up to /altconfig. The root and /config file systems are on the router's flash drive, and the /altroot and /altconfig file systems are on the router's hard drive.
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Caution: After you run the request system snapshot command, you cannot return to the previous version of the software, because the running and backup copies of the software are identical. |
none — Back up the currently running and active file system partitions on the router to standby partitions that are not running.
all-chassis — (TX Matrix and TX Matrix Plus router only) (Optional) On a TX Matrix router, archive data and executable areas for all Routing Engines in the chassis. On a TX Matrix Plus router, archive data and executable areas for all Routing Engines in the chassis.
all-lcc — (TX Matrix and TX Matrix Plus router only) (Optional) On a TX Matrix router, archive data and executable areas for all T640 routers (or line-card chassis) connected to a TX Matrix router. On a TX Matrix Plus router, archive data and executable areas for all T1600 routers (or line-card chassis) connected to a TX Matrix Plus router.
lcc number — (TX Matrix and TX Matrix Plus router only) (Optional) On a TX Matrix router, archive data and executable areas for a specific T640 router (or line-card chassis) that is connected to a TX Matrix router. On a TX Matrix Plus router, archive data and executable areas for a specific T1600 router (or line-card chassis) that is connected to a TX Matrix Plus router. Replace number with a value from 0 through 3.
scc — (TX Matrix router only) (Optional) Archive data and executable areas for a TX Matrix router (or switch-card chassis).
sfc number — (TX Matrix Plus router only) (Optional) Archive data and executable areas for a TX Matrix Plus router (or switch-fabric chassis). Replace number with 0.
as-primary — (J Series routing platform only) (Optional) Create a snapshot that can be used to replace the medium in the primary compact flash drive. This option can be used on the removable compact flash only. The option copies the default files that were loaded on the primary compact flash drive when it was shipped from the factory, plus the rescue configuration if one has been set. This option is useful if you have multiple routers and want to use the same software and configuration on each router. After a boot device is created as a primary compact flash drive, it can operate in only a primary compact flash drive slot. This option causes the boot medium to be partitioned.
config-size size — (J Series routing platform only) (Optional) Specify the size of the config partition, in megabytes. The default value is 10 percent of physical memory on the boot partition. The config partition is mounted on /config, and the configuration files are stored in this partition. This option causes the boot medium to be partitioned.
data-size size — (J Series routing platform only) (Optional) Specify the size of the data partition, in megabytes. The default value is 0 MB. The data partition is mounted on /data. This space is not used by the router, and can be used for extra storage. This option causes the boot medium to be partitioned.
factory — (J Series routing platform only) (Optional) Copy only default files that were loaded on the primary compact flash drive when it was shipped from the factory, plus the rescue configuration if one has been set. After the boot medium is created with the factory option, it can operate in only the primary compact flash drive.
media type — (J Series routing platform only) (Optional) Specify the boot device the software is copied to:
partition — (Optional) Repartition the flash drive before a snapshot occurs. If the partition table on the flash drive is corrupted, the request system snapshot command fails and reports errors. The partition option is only supported for restoring the software image from the hard drive to the flash drive. You cannot issue the request system snapshot command when you enable flash disk mirroring. We recommend that you disable flash disk mirroring when you upgrade or downgrade the software. For more information, see the JUNOS System Basics Configuration Guide.
root-size size — (J Series routing platform only) (Optional) Specify the size of the root partition, in megabytes. The default value is one-third of the physical memory minus the config, data, and swap partitions. The root partition is mounted on / and does not include configuration files. This option causes the boot medium to be partitioned.
swap-size size — (J Series router only) (Optional) Specify the size of the swap partition, in megabytes. The default value is one-third of the physical memory on a boot medium larger than 128 MB, or 0 MB on a smaller boot device. The swap partition is used for swap files and software failure memory snapshots. Software failure memory snapshots are saved to the boot medium only if it is specified as the dump device in the system dump-device configuration hierarchy. This option causes the boot medium to be partitioned.
Before upgrading the software on the router, when you have a known stable system, issue the request system snapshot command to back up the software, including the configuration, to the /altroot and /altconfig file systems. After you have upgraded the software on the router and are satisfied that the new packages are successfully installed and running, issue the request system snapshot command again to back up the new software to the /altroot and /altconfig file systems.
On a routing matrix, if you issue the request system snapshot command on the master Routing Engine, all the master Routing Engines connected to the routing matrix are backed up. If you issue this command on the backup Routing Engine, all the backup Routing Engines connected to the routing matrix are backed up.
You cannot issue the request system snapshot command when you enable flash disk mirroring. We recommend that you disable flash disk mirroring when you upgrade or downgrade the software. For more information, see the JUNOS System Basics Configuration Guide.
maintenance
When you enter this command, you are provided feedback on the status of your request.
user@host> request system snapshot umount: /altroot: not currently mounted Copying / to /altroot.. (this may take a few minutes) umount: /altconfig: not currently mounted Copying /config to /altconfig.. (this may take a few minutes) The following filesystems were archived: / /config
request system snapshot (When Partition Flag Is On)
user@host> request system snapshot partition Performing preliminary partition checks ... Partitioning ad0 ... umount: /altroot: not currently mounted Copying / to /altroot.. (this may take a few minutes) The following filesystems were archived: / /config
request system snapshot (When Mirroring Is Enabled)
user@host> request system snapshot Snapshot is not possible since mirror-flash-on-disk is configured.
request system snapshot all-lcc (Routing Matrix)
user@host> request system snapshot all-lcc lcc0-re0: -------------------------------------------------------------------------- Copying '/' to '/altroot' .. (this may take a few minutes) Copying '/config' to '/altconfig' .. (this may take a few minutes) The following filesystems were archived: / /config lcc2-re0: -------------------------------------------------------------------------- Copying '/' to '/altroot' .. (this may take a few minutes) Copying '/config' to '/altconfig' .. (this may take a few minutes) The following filesystems were archived: / /config