Hi Milkman,
First you should not keep running different Junos in HA devices,It might lead to issues.The best way to upgrade your scenario is connect the usb to the the device running junos 11.
1) remove all the connections on standby device.
2)Go to shell prompt and enter the command ls /dev/,it will show you the possible devices.
3)Mount your USB drive using the following commands
mkdir /tmp/usb
mount -t msdosfs /dev/da1s1 /tmp/usb where /dev/da1s1 is my USB device
4) Enter into the CLI environment and the add the following command
request system software add jinstall-Your-Package-Name.tgz no-validate no-copy
After the process it will ask for system reboot, do it.
when the SRX finished rebooting please reconnect all the disconnected link.
Then check the status by using this comment show chassis cluster status
then check both devices are booting same OS by doing command show system snapshot media internal
You need to make sure both boot partititions are running same os by doing this command request system snapshot slice alternate because junos uses dual partition for redendancy.
Thanks,
Jsree
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