bosboot: missing proto file: /usr/lib/drivers/pci/sissas64_dd

I just upgraded my AIX6.1 NIM server to AIX7 with a DVD I received from my vendor. I noticed that I got an AIX7 TL0 SP1 DVD, which is quite old, so I hoped not to have too much trouble upgrading. Alas.

As the upgrade nearly finished, it asked to load DVD #2, but when I did that, it barfed an error message about some drivers not being able to load. As I had booted from the first DVD, I suspected an error on DVD2 (maybe it was corrupt ?) and switched back to DVD1. Once that was loaded, I was greeted with the following error message :

0301-154 bosboot: missing proto file: /usr/lib/drivers/pci/sissas64_dd

The installation stopped, and I had no other choice than rebooting. But as the bosboot command had failed, no bootable disks were found. Panic ! The only choice I had, it seemed, was to revert to the AIX6 mksysb I luckily had prepared before the upgrade, but I decided to boot the lpar from the AIX7 DVD in maintenance mode and see what I could rescue. After all, only the bootblock was missing.

The missing driver in /usr/lib/drivers/pci/sissas64_dd was indeed missing from the DVD, and it seems that this is a bug in the AIX7 TL0. Fix was provided in TL0SP3.

I decided to try some last command, by copying the /usr/lib/drivers/pci/sissas_dd to sissas64_dd, after which the bosboot command wonderfully worked ! After rebooting the LPAR again, it booted nicely from the bootdisk and I was greeted with the AIX7 login prompt. Pffew !

Querying AIX device attribute values with the AIX kernel debugger

We all know that you can modify online certain attributes on AIX devices, like queue_depth on disks for example :

# chdev -l hdisk15 -a queue_depth=16

However, some attributes changes need a reboot as the device property is in use at that time. You can modify the property by specifying that it will be modified at boot time, with the 'chdev -P' option. This can lead to quite some confusion : imagine a junior sysadmin changing the property, but forgetting the reboot. The 'lsattr' command will report the modified value, but not if it is effectively in use.

We can obtain the currently used value by interrogating the AIX kernel with the kernel debugger, quite a handy feature.
The following command shows the current value of cmd_num_elems on the virtual fiber adapter :

echo vfcs fcs0 | kdb | grep num_cmd_elems 

The following command lists the current values of the queue_depth parameter on hdisk15 :

# echo scsidisk hdisk3 |kdb |grep queue
    ushort queue_depth   = 0x8;


Over the years, I've fallen in love with the AIX multibos command. Here's a little procedure howto test patches without even a reboot of the system :

  • First, clear out all references to old multibos instances :
# multibos -R
  • mount the patch server directory with the patch bundle :
  • # mount nim:/patches /mnt
  • Create a multibos instance of the running kernel and update it :
  • # multibos -Xs
    # multibos -Xac -l /mnt/6100-07-07
  • Check the Standby BOS and review any problems :
  • # multibos -S
    	MULTIBOS> oslevel -s
  • WARNING : adding multibos, will change bootlist, if not wanted, use -t flag :
  • # bootlist -m normal -o
    hdisk0 blv=bos_hd5 pathid=0
    hdisk0 blv=bos_hd5 pathid=1
    hdisk0 blv=hd5 pathid=0
    hdisk0 blv=hd5 pathid=1


    You're one in a million
    that's what you are
    to us so very special
    like a bright shining star !

    On March 24th, we got blessed with a baby daughter Luna, 3.4kg and 52 cm large (small).

    The Hobbit : an unexpected journey

    After the Lord of the Rings trilogy, we have all eagerly been awaiting to venture back to Middle-Earth. Most of the Tolkien fans danced of joy when Peter Jackson announced that the prequel The Hobbit would be poured into 3 movies also. Finally, I had a chance now to see the first part of The Hobbit, called 'An Unexpected Journey'. And it's brilliant.

    A lot of criticism mentioned the slow pace of the movie, but that did not bothered me once. What a beautiful role for Radagast, the odd hermit wizard which hardly got any attention in the Tolkien books. The attention to the Tolkien world has again been so intense, that after the movie I dove into the books to check on some details (who were the two blue Istari which Gandalf says he forgot the names of ? Has Radagast really been into Dol Guldur ? And so on). And Martin Freeman is just brilliant as the young Bilbo, wandering around in the magnificent scenery of New-Zealand.

    Are there no bad points to give out ? Sure, some of the digital hocus-pocus really disappointed, such as the character of Azog, which always remains rubbery and never comes to life. Also, the goblin cave is just a digital splatterfest, and just feels too crammed and noisy onto the screen. The humor that was so prevalent in the book has been cut down drastically so the movie feels a bit too much of Wagnerian proportions. There has also been taken way more freedom into diverging away from the book : Radagast has never been into Dol Guldur and Galadriel was never mentioned in 'The Hobbit'.
    But that's nitpicking.