HPE 9000 and HPE e3000 Servers
Showing results for 
Search instead for 
Did you mean: 

What is IODC

Trusted Contributor

What is IODC


I know it is called I/O Dependnet Code but what does it do?

some of the HP server we have got, has IODC revision 6 but all the workstaions only have IODC revision 0. Is it part of the hardware platform or part of HPUX OS?

the real question is lvlnboot command failed to create swap area on SAN and the error messages is

lvlnboot: Unable to configure swap logical volume.
Swap logical volume size beyond the IODC max address.
ERROR: Command "/sbin/lvlnboot -A n -s /dev/vg00/lvol2" failed.

I read the man page for lvlnboot command and find the following information

"At the HP-UX 11.00 release and forward, the lvlnboot command will support any size dump device depending upon the IODC firmware addressability of the system. If the configured dump logical volume is out of the range of what the firmware can address, the lvlnboot command will return an error message such as "Unable to configure dump logical volume. Dump logical volume size beyond the IODC max address."

All the workstaions already have latest firmware FW5.0. Is it possible to update the IODC itself?

Does SecurePath help?

Stefan Stechemesser
Honored Contributor

Re: What is IODC


it sounds like you have tried to make a swap/dump volume on a device that is not bootable by your workstation.
In this case it makes no sense to set it up as a boot devices.
You could use it a swap mirror, but if your primary disk has failed you will run into trouble when you have to reboot the server.
I think the above error message was implemented to prevent you from accidently setting up such a bad configuration.
The IODC is part of the firmware of your server/workstation. It is not possible to upgrade it seperately like it would be possible on the integrity (IA64) servers and workstations.
You can check if the system firmware is capable of booting from a san by performing a "sea" command in the BCH main menue. If it shows the fibre channel card(s), the IODC can boot via the fc card (another question would be if it really works booting from the SAN).
If it is not possible, I would recomend to use another disk device for at least swap, dump, boot and root device (lvol1,2 and 3 in vg00) to make sure you can boot in case of a disk failure.
I think it should be possible to ignore the error message you saw and use the SAN as a mirror for the internal disks, but as I said, this is not recomended, because you can only restore the bootable disk if it is hot swappable and if you do not have to reboot to restore it.

best regards