I have been playing with a brand new IBM pSeries 610 that arrived early this week. I came preinstalled with minimal AIX 5.1, they even left out the IDE CD-ROM driver the system needs to install any further software. As I wanted to know if they system would work with the AIX from CD-ROM anyways I just booted from CD and this time AIX did have an IDE CD-ROM driver.
This time I installed most of the software I believed we would need. I did not see the option in the install menu to make the 64 bit kernel the default so I ended up with a 32 bit kernel. I had to test our AppleTalk kernel modules in 32 and 64 bit mode so I started with 32. After rebooting in 64 bit mode first I had no NFS mounts, the mount command was barfing that one of the NFS kernel modules is using an old obsolete format. Appearently I installed one package to much, after removing the des package NFS works fine.
The AppleTalk kernel module was an easy port, just Makefile adaptions to compile a 32 bit as well as a 64 bit module from the same sources and archive these together into an ar archive. The AIX kernel is smart enough to select the proper version from the archive depending upon the mode it is running in, pretty nifty.
While testing some stuff in 64 bit mode I noticed that Apache (as delivered by IBM as Websphere server) did core dump upon starting. Dbx does tell me the core file is invalid, strange. I started httpd with dbx and the -X option and dbx did hang. I kill -9'ed httpd and could exit dbx. I then attempted an apachectl start and whoops, I was talking with the service processor instead of AIX (I was sitting at the console). I rebooted and looked at the generated vmcore file and it did point at the kernel based linker that AIX uses for its shared libraries, it appeared to have stumbled across a NULL pointer while loading an httpd module.
A few of the other subsystems also produce strange failure messages in 64 bit mode, all in all I am not convinced about AIX 5.1 64 bit. AIX has been rock solid for me since the early beginnings, this is really disappointing. I looked at the AIX fixes page and tried the new order system for AIX 5 fixes as I found out that I did not yet have the latest components. One does click on the packages needed and they did tell me they would process my order and send me a notification with a download URL. After a few hours waiting no URL yet, not encouraging.