VxRail: File-based Backup Stops After Upgrade

Summary: After a VxRail upgrade, the file‑based backup runs but leaves empty logs and no compatible backups because the crontab still calls the python interpreter instead of mcp_python, causing failure. ...

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Symptoms

The following indicators appear after a VxRail code upgrade.

  • No compatible backup files are present after the upgrade.
vx_mgr:/var/log # mcp_python /mystic/vxm_backup_restore/vxm_backup_restore.py -l 
Current user is root. We can do current job. 
Starting to get authentication info. 
Connecting to vCenter [vc_fqdn] 
Fetched node_sn ['node1', 'node2', 'node3'] 
Download vxmbackup.json from datastore. 
datacenter path is /VxRail-Datacenter download file http_url: https://vc_fqdn/folder/VxRail_backup_folder/vxmbackup.json?dsName=VxRail-Virtual-SAN-Datastore-<cluster id>&dcPath=%2FVxRail-Datacenter
Found 3 VxRail backup item(s) 
1) VxRailArchive_20241216125738_28492386.tgz(Incompatible: version not compatible) 
2) VxRailArchive_20241216131518_28492386.tgz(Incompatible: version not compatible) 
3) VxRailArchive_20241216133018_28492386.tgz(Incompatible: version not compatible)
  • The system "messages" log records the backup start at the scheduled time.
2024-12-16T17:15:01.885958+00:00 vx_mgr CRON[19682]: (root) CMD (/usr/bin/logger 'VxM rotation backup start.' && python /mystic/vxm_backup_restore/vxm_backup_restore.py -b) 
2024-12-16T17:15:01.932592+00:00 vx_mgr root: VxM rotation backup start. 
2024-12-16T17:15:02.120986+00:00 vx_mgr CRON[19680]: (root) CMDEND (/usr/bin/logger 'VxM rotation backup start.' && python /mystic/vxm_backup_restore/vxm_backup_restore.py -b)
  • The VxRailBackupRestore.log file is zero bytes and remains empty.
vx_mgr:/home/mystic # ls -lh /var/log/mystic/VxRailBackupRestore.log 
--w----r-T 1 root root 0 Dec 16 18:50 /var/log/mystic/VxRailBackupRestore.log  

vx_mgr:/home/mystic # cat /var/log/mystic/VxRailBackupRestore.log  
vx_mgr:/home/mystic #
  • Running the backup script with the generic python interpreter shows a usage message.
vx_mgr:/var/log # python /mystic/vxm_backup_restore/vxm_backup_restore.py -b 
Usage of the script: mcp_python /mystic/vxm_backup_restore/vxm_backup_restore.py
  • The crontab entry still references the old python command.
vx_mgr:/var/log # cat /etc/cron.d/vxm_schedule_backup 
0 0 * * * root /usr/bin/logger 'VxM rotation backup start.' && python /mystic/vxm_backup_restore/vxm_backup_restore.py -b

Cause

VxRail Manager internal Python environment changed in newer releases. The backup script must be executed with mcp_python to load the correct packages.

Legacy crontab entry

File‑based backup jobs created on releases prior to 7.0.520 or 8.0.300 reference the generic python interpreter in the OS crontab. After an upgrade, this interpreter no longer provides the required environment, causing the script to fail.

Impact across versions

  • Upgrades from any version before 7.0.520 to 7.0.520 or later.
  • Upgrades from any version before 8.0.300 to 8.0.300 or later.
  • Upgrades from any version before 7.0.520 directly to 8.0.300 or later.

Resolution

Resolution Steps

  • Reconfigure the file‑based backup to use mcp_python as the interpreter. Perform the appropriate command as the root user: 
    mcp_python /mystic/vxm_backup_restore/vxm_backup_restore.py -c

     

    For VxRail 8.0.370 and later:

    mcp_python /mystic/vxm_backup_restore/vxm_backup_restore_limited_bandwidth.py -c

 

For additional reference, see the VxRail Administration Guides:

Table 1: Relevant Administration Guides
Document Description
VxRail 8.0.x Administration Guide Provide a general description of VxRail, how it works, and customer‑facing administrative tasks.
VxRail 7.0.x Administration Guide Provide a general description of VxRail, how it works, and customer‑facing administrative tasks.

Affected Products

VxRail, VxRail Appliance Series, VxRail Software
Article Properties
Article Number: 000260789
Article Type: Solution
Last Modified: 20 Jul 2026
Version:  6
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