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  • 1.  Storage partitions on QFX 5100 series ?

    Posted 07-19-2019 01:56

    I just realized the command "show system storage partitions" does not work on QFX while it does on EX series switches.

    Can someone point me to a article explaining why this does not work / what happened with storage partitions on QFX switches ?

    Thank you.



  • 2.  RE: Storage partitions on QFX 5100 series ?

     
    Posted 07-19-2019 04:16

    Hi Lacko,

     

    QFX5100 has a virtualized control plane,  the Junos boots up as a Virtual Machine and is the only slice available on the device instead of SW partitions.

     

    Partition is a concept where the storage is divided into partitions. Junos loads from one partition and a snapshot of it can be copied to the other partition. In case of corruption, we can try to load the Junos from the backup partition. This concept does not exist on the QFX5100 which as explained loads Junos as a VM host(KVM).

     

    However, you can take a snapshot of the existing Junos on QF5100 into a external media(usb) and can use to recover if Junos is corrupted. On the EX device, you copy the working snapshot to the other partition and use it boot the device.

     

    The same goes with EX4600 which is similar to QFX5100.

     

    Hope this helps.

     

    Thanks,
    Pradeep
    Please Mark My Solution Accepted if it Helped, Kudos are Appreciated too!!!

     

     



  • 3.  RE: Storage partitions on QFX 5100 series ?

    Posted 07-19-2019 05:27

    Thank you @pradkm for your answer, this really explains the situation.



  • 4.  RE: Storage partitions on QFX 5100 series ?
    Best Answer

     
    Posted 07-19-2019 04:18

    Hi lacko,

     

    In QFX5100, the hardware are managed mostly by Host OS (Linux) and Junos runs as a VM.   The host system has two SSD storage devices, each with 16 GB of capacity. From the partition layout perspective, QFX5100 will be running the Linux Volume Manager (LVM).


    There are two 16 GB SSDs, which are part of the Linux LVM. The primary volume group is vg0_vjunos.  This volume group has three volumes that are used by Junos:
    • lv_junos_recovery
    • lv_var
    • lv_junos

     

    You can see the two disks as /dev/sda and /dev/sdb using these commands:

    request app-engine host-shell
    fdisk -l

     

    Example:

    {master:0}
    root@JNPR_QFX5100> request app-engine host-shell 
    Last login: Wed Jul 17 18:23:15 from 192.168.1.2
    --- Host 14.1X53-D40.8 built 2016-11-10 02:56:31 UTC
    -sh-4.1# fdisk -l
    
    Disk /dev/sda: 16.0 GB, 16013852672 bytes
    255 heads, 63 sectors/track, 1946 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x000214ab
    
       Device Boot      Start         End      Blocks   Id  System
    /dev/sda1   *           1         125     1000000   83  Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sda2             125        1857    13914062+  83  Linux
    
    Disk /dev/sdb: 16.0 GB, 16013852672 bytes
    255 heads, 63 sectors/track, 1946 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x000600f6
    
       Device Boot      Start         End      Blocks   Id  System
    /dev/sdb1   *           1         125     1000000   83  Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sdb2             125        1857    13914062+  83  Linux
    
    Disk /dev/mapper/vg0_vjunos-lv_junos: 12.9 GB, 12884901888 bytes
    255 heads, 63 sectors/track, 1566 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    
    
    Disk /dev/mapper/vg0_vjunos-lv_junos_recovery: 4294 MB, 4294967296 bytes
    255 heads, 63 sectors/track, 522 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    
    
    Disk /dev/mapper/vg0_vjunos-lv_var: 11.3 GB, 11307843584 bytes
    255 heads, 63 sectors/track, 1374 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000

    Read more on this from the nice reference here:

    https://forums.juniper.net/t5/Ethernet-Switching/QFX5100-architecture-hardware-and-flow-process/td-p/295819

     

    Hope this helps.

    Regards,
    -r.

    --------------------------------------------------

    If this solves your problem, please mark this post as "Accepted Solution."
    Kudos are always appreciated :).



  • 5.  RE: Storage partitions on QFX 5100 series ?

    Posted 07-19-2019 05:28

    Thank you @mriyaz for the detailed description, I appreciate.