HP Integrity Virtual Machines 4.2: Installation, Configuration, and Administration

• migrate_init_phase_timeout — Specifies the maximum number of seconds the online
migration spends during the initialize phase of the migration. The default is 10 seconds.
• migrate_copy_phase_timeout — Specifies the maximum number of seconds the online
migration spends during the full-copy phase. The default is infinite.
• migrate_io_quiesce_phase_timeout — Specifies the maximum number of seconds the
migration spends during the quiesce phase. The default is 15 seconds.
• migrate_frozen_phase_timeout — Specifies the maximum number of seconds the migration
spends during the freezing phase. The default is 60 seconds.
10.3.3.2 Migrations Might Time Out and Need to be Restarted
To protect a guest's workload, the Online VM Migration feature has limits for the amount of
time that a migrating guest can remain in various phases of a migration. There are several capacity
and resource-related reasons an attempted online migration might time out and abort, leaving
the guest running on the source host. Potential causes include:
• Insufficient resources on the target host
• Excessively busy VM Hosts
• A slow network connection
• An extremely busy guest
If conditions like these exist, the attempted migration is aborted , so the guest's workload can
continue running on the source VM Host. This is not a serious problem, because the guest
continues to run on the source, and the migration can be re-attempted when conditions improve.
10.3.3.3 Guest Storage Device Shareable Attribute not Propagated During Online Migration
The guest storage device shareable attribute is not propagated to the target VM Host during an
online migration. After the first guest that is configured to use the shared storage is online
migrated to the target, enable the shared attribute for the device to avoid online migration failures
for other guests that share the device. Use the hpvmstatus command to determine the device
special filename of the shared device on the target and the hpvmdevmgmt command to mark the
device shareable. For example:
hpvmstatus -P vm_name -d
hpvmdevmgmt -m gdev:/dev/rdisk/disknnn:attr:SHARE=YES
For online and offline migration, device special files (DSFs) assigned to virtual machines do not
need to match on source and target VM Hosts. Do not physically rearrange controllers on the
host systems to make the paths the same. This can lead to stale DSFs and stale entries in the
Integrity VM device management database. The hpvmmigrate command converts from DSF
on the source VM Host to WWID and then DSF on the target VM Host. Use ioscan -C disk
-P wwid to see if the virtual machine's disks are presented to both VM Hosts If you find stale
DSFs and stale entries in your Integrity VM device management database, use the insf -e
command and the hpvmdevmgmt command to repair the HP-UX VM Host system.
Do not mark disks SHARE=YES for devices assigned to virtual machiness that will migrate (unless
more than one virtual machine will share the storage on the same VM Host). Marking a device
SHARE=YES can lead to more than one virtual machine using the device at the same time and
can lead to disk corruption.
10.3.3.4 Using NTP on the VM Guests
Using NTP is strongly recommended for Online VM Migration environments. Each guest should
include all potential VM Hosts as servers in its ntp.conf file so the current local VM Host can
be used as a time source. Whether migrating or not, guests should not be used as time servers.
To maintain reliable time synchronization on a guest, it might be necessary to reduce the NTP
polling interval, so the guest checks the time more frequently with the NTP server.
180 Migrating Virtual Machines