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Setting Up Network To Improving Partition Mobility Performance



Setting Up Network To Improving Partition Mobility Performance


Can I control the network interface that is used for Migration? As of the writing of this document there is no interface on the HMC to directly control the interface.
When the migration is started by the controller it specifies an IP address for the remote system.
The IP address that is provided by the HMC is the address being used for the RMC connection to the VIOS.

It is possible to specify an IP address using the command line. For example,

migrlpar -o m -t [TARGET_SYSTEM_NAME] --id 2 --ip [TARGET_IVM_HOSTNAME] -u padmin -i source_msp_ipaddr=,dest_msp_ipaddr=

This will migrate partition (id = 2) from the system on which this is run to the target system.
All communication between the source and target VIOS partitions will be done using the source and target msp_ipaddr.

There is a work around that will allow for traffic to be routed over a specific interface.
By creating a host route on the VIOS partitions it is possible to direct the traffic to flow
over a selected interface. Creating a host route does have the effect of directing all traffic
destined for the remote VIOS to also be sent over the specified interface.
Referring to the picture, set up the routes using these commands:


- Make sure switch is enabled to accept the speed of adapter.

-  Example, If: ipaddress  (1) = ; (2) = ; (4) = ; (3) =

Referring to the picture, set up the routes using these commands:

On System #1 using TCP/IP addresses for enX on System #2
$ chdev -dev inet0 -attr route=”host,<en2 address (1)>,<en3 address (2)>”
$ chdev -dev inet0 -attr route=","

On the VIOS on System #2
$ chdev -dev inet0 -attr route=”host,<en2 address(3)>,<en3 address (4)>”
$ chdev -dev inet0 -attr route=","


Currently transfer of data for 1 partition does not scale much
beyond 1 Gbit speed, 10Gibt does not provide benefit for
parallel migrations.

Calculating Speed:


ftp > put "| dd if=/dev/zero bs=32k count=100000" /dev/null
Detailed Test:
Theoretical Values:
Gigabit per second = 1,000,000,000  bits per second
1,000,000,000 / 8 = 125,000,000 Bytes/s
125,000,000 / 1024 = 122070.3125 KBytes/s

Practical approximately 80% of theoretical.

Network interface selection for mover service partitions (MSP)
with multiple interfaces

If multiple network interfaces are available on a MSP, it is now possible via HMC command line to select which IP address the mover will use to transport client partition data during a live partition mobility event. HMC level V7r3.5.0 or later is required for this function.

To return a list of possible source and destination MSP pairs, from HMC, type the following command:

hscroot@hmc:->lslparmigr -r msp -m migfspL2 -t migfspL1 --filter lpar_names=mig_lpar_name

Related information

Live Partition Mobility
IBM PowerVM Live Partition Mobility Redbook
IVM lslparmigr command

Original publication date


Document information

More support for: Virtual I/O Server

Software version: 5.3, 6.1

Operating system(s): AIX

Software edition: Standard

Reference #: T7000117

Modified date: 2010-01-20