Friday, 13 December 2013

Migrate sun4u to sun4v using FLAR

FLAR stands for FLash ARchive. If we need to install a few Solaris servers and customize them in a similar way.
Instead of installing and configuring one by one, we can install and configure one server first, then create FLAR on this server, and install the other servers using this FLAR.
FLAR can also be used for server migration.

The steps of creating FLAR and installing from FLAR is very straight forward. However if we are migrating from servers with older CPU to servers with different CPU architecture, we have to do some extras steps.
Recently I migrated a few servers from sun4u to sun4v using FLAR, Here are my migration steps:
create FLAR image on sun4u server
  1. By default FLAR created on sun4u cannot be used on sun4v servers, we have to add sun4v as a supported architecture for FLAR.
    # echo "PLATFORM_GROUP=sun4v" >> /var/sadm/system/admin/.platform

    # flarcreate -n "migration flar" -c -S -x /flar -x /export/home /flar/migration.flar

    Alternatively we can add -U flag to create FLAR with sun4v support
    # flarcreate -n "migration flar" -U "content_architectures=sun4u,sun4v" -c -S -x /flar -x /export/home /flar/migration.flar

  2. Verify our FLAR can be used on sun4v machines:
    # flar -i /flar/migration.flar | grep content_architectures
  3.  Now move the FLAR to a storage accessible from sun4v machines, this can either be NFS, HTTP, or a local hard drive.
  4. Boot sun4v machine, choose Flash Install, and select the migration.flar we created in step 1.
  5. After installation completes, reboot server, we will get this error:
    cannot open boot_archive
  6. To boot the server properly, we need to upgrade the sun4v machine:
    boot sun4v machine from DVD or Jumpstart, select Upgrade, after upgrade finishes, reboot server.
We have successfully migrated sun4u to sun4v machine!