These minor alarms for "VMHost RE<0 or 1> Disk 1" and "VMHost RE<0 or 1> Disk 2" were caused by version mismatch between RE0 and RE1. This issue can be resolved when both REs run on the same version of software.
In this example, RE0 is the primary running release 16.1R7.7 and RE1 is the backup with 15.1F7.3. The alarm was reported on primary RE0:
labroot@example-re0> show chassis alarms 2 alarms currently active Alarm time Class Description 2019-04-04 16:54:09 PDT Minor VMHost RE 1 Disk 2 2019-04-04 16:54:09 PDT Minor VMHost RE 1 Disk 1 labroot@example-re0>
Message logs for this alarm:
Apr 4 16:54:09.786 example-re0 alarmd[18862]: Alarm set: RE color=YELLOW, class=CHASSIS, reason=VMHost RE 1 Disk 1 Apr 4 16:54:09.786 example-re0 alarmd[18862]: Alarm set: RE color=YELLOW, class=CHASSIS, reason=VMHost RE 1 Disk 2 Apr 4 16:54:09.829 example-re0 craftd[18240]: Minor alarm set, VMHost RE 1 Disk 1 Apr 4 16:54:09.842 example-re0 craftd[18240]: Minor alarm set, VMHost RE 1 Disk 2 labroot@example-re0> show version invoke-on all-routing-engines | match "re0|re1|Junos: " re0: -------------------------------------------------------------------------- Hostname: example-re0 Junos: 16.1R7.7 re1: -------------------------------------------------------------------------- Hostname: example-re1 Junos: 15.1F7.3 labroot@example-re0> labroot@example-re0> show chassis hardware | match routing Routing Engine 0 REV 09 740-031116 9009184326 RE-S-1800x4 Routing Engine 1 REV 12 740-031116 9009247395 RE-S-1800x4 labroot@example-re0>
Junos version mismatch between RE0 and RE1 is the cause of such alarms VMHost RE < 0 or 1> Disk <1 or 2> .
Upgrade the backup RE1 to the same version as primary RE0.
In this example, RE1 was running 15.1F7.3 and should be upgraded to the same 16.1R7.7 version as the primary RE0. After RE1 software is upgraded to the 16.1R7.7 there is no more alarms.
labroot@example-re1> request system software add junos-install-mx-x86-64-16.1R7.7.tgz force reboot no-validate Verified junos-install-mx-x86-64-16.1R7.7 signed by PackageProductionEc_2018 method ECDSA256+SHA256 ... --- JUNOS 16.1R7.7 Kernel 64-bit JNPR-10.3-20180601.93ff995_buil labroot@example-re1> labroot@example-re0> show chassis alarms No alarms currently active labroot@example-re0> labroot@example-re0> show version invoke-on all-routing-engines | match "re0|re1|junos:" re0: -------------------------------------------------------------------------- Hostname: example-re0 Junos: 16.1R7.7 re1: -------------------------------------------------------------------------- Hostname: example-re1 Junos: 16.1R7.7 labroot@example-re0>