HP vPars and Integrity Virtual Machines V6.1 Administrator Guide

If a VSP is reinstalled at some point after using the secsetup script to configure SSH keys, you
might receive warning messages from ssh commands about keys changed, or bad keys in your
known_hosts file. In this case, use the ssh-keygen -R hostname command to remove
obsolete keys from the known_hosts file, and then use the secsetup command again to configure
new keys.
If you set up SSH security between VSPs before adding the conventional —hpvm-migr host alias
to the /etc/hosts file and you do not run secsetup on the host-alias addresses, the
hpvmmigrate command fails with the message, Host key verification failed, when
it attempts to use the conventional host alias.
A workaround is to run SSH once manually (for example, ssh -hpvm-migr date) and enter yes
to the question about whether or not you should continue. This action adds -hpvm-migr to the
list of known hosts, and subsequent hpvmmigrate commands will find the proper host key.
12.3.3.2 Using a Third-Party SSH
The HP-UX native SSH is assumed. To use an incompatible SSH command with the hpvmmigrate
command, make sure your version of SSH is set up for host-based authentication without requiring
interactive passwords. Then set the SSHEXECPATH environment variable (in /etc/rc.config.d/
hpvmconf) to invoke a command or shell script similar to the one provided in alt_ssh_example.
Customize alt_ssh_example script for use in your environment with your version of SSH to
translate all the HP-UX SSH specific options to execute your alternate SSH command and to achieve
similar behavior. The command, or shell script, must have permissions similar to a real ssh
executable -- it should be writable only by the file owner. The hpvmmigrate command expects
to use the HP-UX ssh command as in the following:
ssh -e none -o BatchMode=yes -T -x target-host-alias exec hpvmmigrate -#
See the alt_ssh_example comments for explanations of the -e, -o, -T, and -x options.
With an alternate version of SSH, you might not need some of the HP-UX specific options; or, there
may be different options that achieve the same effect; or, perhaps some alternate SSH configuration
mechanism can be used eliminating the need for some of the HP-UX specific SSH options.
12.3.4 Virtual machine requirements and setup
Online VM Migration is supported on HP-UX 11i v2 and HP-UX 11i v3 guests. All memory sizes
and virtual CPU configurations for the current version of Integrity VM are supported. As with all
guest OS installations, the guest kit should be installed. With V6.1, if VirtualBase B.06.10 is
installed on the guest, the guest kit does not need to be installed.
12.3.4.1 Setting online migration phase time-out values
Various things can cause and online migration to abort: insufficient resources on the target host,
busy source or target hosts a slow private network connection, an excessively busy guest, and so
on. When a migration aborts, the guest continues to run, unaffected, on the source VSP. Therefore,
these are not serious errors. You can attempt the online migration again when the blocking
conditions improve.
To protect the guest's workload, the online migration software limits the amount of time spent in
each migration phase. The phases of an online migration are:
• Initialization phase — Establishes connections, various checks, starts the target guest, and so
forth.
• Copy phase — Tracks writes to guest memory and copies all of guest memory.
• I/O quiesce phase — Queues new I/O requests and waits for outstanding I/O to complete.
• Frozen phase — Stops the virtual CPUs and copies modified memory and guest state.
12.3 VSP and virtual machine configuration considerations 211