To recover a primary compact flash disk with a corrupt or missing operating system, you must copy a special JUNOS software image directly to an unformatted (raw) device. Recovery images are available from the same location as normal J-series software upgrades. (See Downloading Software Upgrades from Juniper Networks.)
The images use the naming convention junos-jseries-release-cfnnn.gz, where release is the software version and nnn is the target compact flash disk size in megabytes—128, 256, or 512.
To recover a primary compact flash disk:
The uncompressed image must have the same size as the target compact flash capacity: 128 MB, 256 MB, or 512 MB.
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You must use the correct target device name. Failure to do so might damage other storage devices connected to the host PC. |
root# dd if=junos-jseries-7.0–20041028.0–export-cf128
of=/dev/hde
250368+0 records in250368+0 records out
C:\> physdiskwrite —u junos-jseries-7.0–20041028.0–export-cf512
physdiskwrite v0.5 by Manuel Kasper
Searching for physical drives...
Information for \\.\PhysicalDrive0:
Windows: cyl: 2432
tpc: 255
spt: 63
C/H/S: 16383/16/63
Model: HITACHI_DK23DA-20
Serial number: 123ABC
Firmware rev.: 00J2A0G0
Information for \\.\PhysicalDrive1:
Windows: cyl: 125
tpc: 255
spt: 63
Which disk do you want to write? (0..1) 1
WARNING: that disk is larger than 800 MB! Make sure you're
not accidentally overwriting your primary hard disk!
Proceeding on your own risk...
About to overwrite the contents of disk 1 with new data.
Proceed? (y/n) y
511451136/511451136 bytes written in total
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The copy process can take several minutes. |
After copying the image to the compact flash disk, you can use it as the primary compact flash disk in any J-series Services Router. For installation instructions, see the J-series Services Router Getting Started Guide.