AIX Live Update
Starting with AIX Version 7.2, the AIX operating system provides the AIX Live Update function which eliminates downtime associated with patching the AIX operating system. Previous releases of AIX required systems to be rebooted after an interim fix was applied to a running system. This new feature allows workloads to remain active during a Live Update operation and the operating system can use the interim fix immediately without needing to restart the entire system. In the first release of this feature, AIX Live Update will allow customers to install interim fixes (ifixes) only. Ultimately it may be possible to use this function to install AIX Service Packs (SPs) and Technology Levels (TLs) without a reboot.
IBM delivers kernel fixes in the form of ifixes to resolve issues that are reported by customers. If a fix changes the AIX kernel or loaded kernel extensions that cannot be unloaded, the host logical partition (LPAR) must be rebooted. To address this issue, AIX Version 7.1, and earlier, provided concurrent update-enabled ifixes that allowed deployment of some limited kernel fixes to a running LPAR. Unfortunately not all ifixes could be delivered as “concurrent update-enabled”. The AIX Live Update solution is not constrained by the same limitations as in the case of concurrent update enabled ifixes. The AIX 7.2, Live Update feature will allow customers to install ifixes without needing to reboot their AIX systems, avoiding downtime for their mission critical, production workloads.
This article (in the link below) will discuss the high-level concepts relating to AIX Live Updates and then provide a real example of how to use the tool to patch a live AIX system. I was fortunate enough to take part in an Early Ship Program (ESP) for AIX 7.2. During the ESP I had the opportunity to test the AIX Live Update feature. I’ll share my experience using this tool in the example that follows.