Drupal SSO: An unsupported mechanism was requested…

Here is a step that may help You to debug the error above.

Today I was setting up SSO on a Drupal page against MS AD. Something went wrong and I found the following message in site’s error_log:

gss_accept_sec_context() failed: An unsupported mechanism was requested (, Unknown error)

Let’s modify a little bit apache’s config, and add this to appropriate place (global or vhost level):

 LogLevel debug

Restart apache and check the log again:

kerb_authenticate_user entered with user (NULL) and auth_type Kerberos
Acquiring creds for HTTP/intranet.kesz.hu@KESZ.HU
Verifying client data using KRB5 GSS-API
Client didn't delegate us their credential
Warning: received token seems to be NTLM, which isn't supported by the Kerberos module. Check your IE configuration.
GSS-API major_status:00010000, minor_status:00000000
gss_accept_sec_context() failed: An unsupported mechanism was requested (, Unknown error)

So the real problem was: Warning: received token seems to be NTLM, which isn’t supported by the Kerberos module. That is much more informative than the unknown error we had before!

Dont forget to set back LogLevel after You finished because the log file fast becomes really large…

hpacucli error: no controllers detected.

I would like to check my P400 controller inside a HP DL180 G5 ProLiant server which was running x64 Linux with 2.6.31.6 kernel. HP has a utility named hpacucli designed for this kind of task so I was looking for appropriate download link. After found some versions (I newer understood the logic behind HP’s software version numbering) and downloaded them I realized that neither of them was seeing my P400 controller:

root@xerxes:~/opt/compaq/hpacucli/bld# ./.hpacucli ctrl all show

Error: No controllers detected.

The Internet is full with solutions to this problem:
– Use uname26 utility to hide Your 3.x kernel! But I have 2.6…
– modprobe sg before hpacucli! Sg was compiled into kernel already…
– etc…

After some hours of trials I was strace-ing the hpacucli command and found that it tries to open it’s libcpqimgr which was placed in the same directory but not in LD_LIBRARY_PATH, so it didnt found it. So “No controllers detected” actually means “Hey guy, I didnt find my right hand which I can use for detecting controllers!”. Nice.

Little modification to command line:

root@xerxes:~/opt/compaq/hpacucli/bld# LD_LIBRARY_PATH=. ./.hpacucli ctrl all show

Smart Array P400 in Slot 6                (sn: PAFGL0M9VWK002)

I understand that if I installed the package and used the appropriate script provided by HP I never met this situation. So this is an unexpected thing. But maybe others run into same so remember: strace is (one of) Your best (non human) friends!