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junos booted from secondary storage....

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  • 1.  junos booted from secondary storage....

    Posted 11-10-2013 06:07

    on one of my ex series sw,,im finding msg

    junos bootedd from secondary storage..primary may be failed...


    what other options command do i have except reinstalling junos firmware....

    like is there some command to copy firmware from secondary storage to primary storage???





  • 2.  RE: junos booted from secondary storage....

    Posted 11-10-2013 10:12

    You can use 


    request system snapshot slice alternate

  • 3.  RE: junos booted from secondary storage....

    Posted 11-10-2013 23:19

    hi smicker

    i tried same and got fol output...

    Formatting alternate root (/dev/da0s1a)
    Copying '/dev/da0s1a' to '/dev/da0s1a' .. (this may take few minutes)
    The following filesystems were archived:/

    (i dont know what all it copied drom which partition to which other..can u plz explain..whtat this comand is doing exactly)

    however still on rebooting,,issue was not resolved it i got same msg that junos booted from secondary image...

  • 4.  RE: junos booted from secondary storage....

    Posted 11-11-2013 00:04

    i have got a detailed reply on it from juniper knowledge base by searching...




    it satisfies my query

  • 5.  RE: junos booted from secondary storage....
    Best Answer

    Posted 11-14-2013 11:26

    The command is basically archiving whole stuff (configuration file and juons image) from the partition on which it got boot image to alternate  partition. Improper shutting down of device or hard restart may cause the image in primary partition to get corrupted and on next boot device will get boot image from secondary partition and at login following message will be displayed (*junos booted from secondary storage.Primary may be failed). Now solution is to archive the current boot partition to alternate partition which was earlier primary partition but image got corrupted due to some of the reason.

    >request system snapshot media internal slice alternate

    but even after that * same error message will be displayed again and again on every restart as juons has set the boot partition for itself from which it got boot image after primary privation got corrupted. Now issue following command

    . >request system reboot media internal slice alternate

    and the message will disappear

    This concept is knows as Resilient Dual-Root Partitions and introduced in Juons 10.4R3. Actually idea behind is to provide resiliency on devices which got its boot image corrupted due to power outage and require serial console for juons re installation. Also visit http://www.juniper.net/techpubs/en_US/junos/topics/concept/switch-resilient-dual-root-partitions.html


    Pleas mark this as accepted solution if it solves your problem

    A Junos is good way of appreciation


    Kashif Nawaz

    JNCIP-Sec, JNCIS-Sec, JNCIS-Ent, JNCIA-Junos

  • 6.  RE: junos booted from secondary storage....

    Posted 11-14-2018 04:23


    I have done several times the official procedure from Juniper to solve this issue and every time the switch reboot with the backup partition despite of follow the link instructions:


    I have more than 300 ex switches and every week I have the same issue with any of the switches, If there is a power problem, the switch reboots with the backup partition.


    can anyone help me with this problem?