Edit: I will miss sharing these tips and tricks
Originally posted November 5, 2019 on AIXchange
IBM Support troubleshoots an NPIV client boot hanging with Error Code 554.
On Twitter Chris Gibson highlighted an IBM Support document that troubleshoots an NPIV client
boot hanging with Error Code 554, which I’ve excerpted below:
“AIX NPIV Client Boot Hanging with Error Code 554 due to max_xfer_size
Cause
This is cause [sic] by client’s max_xfer_size setted too high compared to VIOS Fiber Physical Adapter
Environment
AIX & NPIV
Diagnosing The Problem
To confirm the boot failure is due to max_xfer_size’s value too high on AIX Client, perform a Boot Debug on AIX Client.
To enable this Boot Debug follow guidance:
http://www-01.ibm.com/support/docview.wss?uid=isg3T1019037
Then trap the following message: “open of /dev/fscsi0 returned 61“
Resolving The Problem
Boot AIX client partition in Maintenance Mode, put back max_xfer_size value equal or lower to the one configured on the VIOS… .
Then you can set this value in AIX Client ODM (Maintenance Mode) with chdev command and perform a normal Boot.
Another way to address this would be to change “max_xfer_size” on Physical HBA to match Client’s one, but this change require VIOS’ reboot. This way seems more risky if one of LPARs is not fully operational from Multi-Pathing perspective.”
Be sure to read the entire thing.
I love sharing these tips for a couple of reasons. One is self-interest. Many times when I need information on an issue, my web search will return one of my long-forgotten AIXchange posts. And hopefully by raising these issues here maybe you’ll think of this post and/or that document, or you’ll simply remember to avoid making the max_xfer_size too high in the first place.