Upgrading server operating systems is a serious undertaking. Yes, you gain access to important new features and safeguards – but your mission-critical data is at risk throughout the upgrade and migration process.
With the release of Solaris 11.4, Oracle also made upgrading from previous 10.0 versions more difficult. Initially, there was no direct upgrade available. The move from SVR4 packaging to IPS packaging in Oracle Solaris 11, means that a direct update is not possible.
Instead, Oracle Solaris 10 images had to be hosted on Solaris 11.4 in a “solaris10” branded zone. This was known as an Oracle Solaris 10 Container – and your server image did not benefit from all the new features of the 11.4 upgrade.
The good news is that things have changed.
Realising that this was far from ideal for their customers, Oracle has released a new tool to assist with migration – sysdiff. sysdiff is a python script that automatically analyses a solaris10 branded zone and creates an IPS package from all the non-OS files it finds there. The package can then be installed natively in the 11.4 OS.
At the most basic level, the migration process can now be completed in three steps:
1. Migrate Solaris 10 applications to a solaris10 branded zone on the target server (running Solaris 11.4).
2. Run the sysdiff script to create a new IPS package of the contents of the solaris10 zone.
3. Install the new IPS package on the 11.4 server native or kernel zone to enjoy all the benefits of the new OS.
Sysdiff does invite manual intervention at each stage of the migration process so you can adjust the list of files included in the IPS package if required.
Oracle is keen to stress that they regard the sysdiff migration process as an avenue of last resort. Instead, they recommend installing an 11.4 version of the application and migrating data via traditionally supported means.
sysdiff works great
Despite these dire warnings, the evidence is that sysdiff does a very good job of migrating workloads effectively. And don’t forget – the Oracle Solaris binary guarantee still applies.
It’s important to note that sysdiff is not yet included with Solaris 11.4. Although created by Oracle engineers for their customers, it is not yet regarded as an “official” tool. If your in-house team wants to test the script (or use it for a production upgrade), they will need to download it from the Oracle Solaris Github contrib area. On a more positive note, the script is well documented, making the upgrade process relatively straightforward.
If you do try the script and find it useful, make sure you provide feedback for the Oracle team. This will not only encourage further development of sysdiff but may also see the tool included as standard with future Solaris upgrades and patches.
For assistance and advice on upgrading the Solaris operating system, or for help using sysdiff to perform an application migration, please do not hesitate to give the WTL team a call.