[OpenAFS] Active Directory 2003, kerberos 5, openAFS - rxkad error=19270407, arghhhh

John W. Sopko Jr. sopko@cs.unc.edu
Tue, 09 Jan 2007 17:28:01 -0500

Jeffrey Altman wrote:
> John W. Sopko Jr. wrote:
>> In C:\Program Files\Support Tools\ktpass
>> right click properties "version tab" shows 5.2.3790.1830
>> So use ktutil on the linux openafs server, setting the
>> password the same as the afs users Windows password:
>> eagle/root [/usr/afs/etc] # ktutil
>> ktutil:  add_entry -password -p afs/cs.unc.edu@MSE.UNCCS.TEST -k 1 -e
>> des-cbc-crc
> Where did you get the key version number of 1 from?

When I ran the "bad" ktpass command on windows it always generates kvno 1
by default. The ktpass /? (help) says:

kvno : Override Key Version Number
        Default: query DC for kvno.  Use /kvno 1 for Win2K compat.

Since this Windows 2003 server is running in 2000 mixed mode I thought
it forced/kept the kvno at 1 for w2k compatability. Below is the output of
the ktpass, no matter how many times I run it it keeps the "vno"
at 1. I check the keytab.mse file with ktutil and it is at 1.

But you are right I do not know what is in the server. I did not
think hard enough about this.

 > The key version number must match the number that is actually
 > issued by the KDC.  You can identify the version number using
 > the MIT Kerberos utility
 >   kvno <principal>

I tried this to get the kvno:

eagle/root [/usr/afs/etc] # kinit afs
Password for afs@MSE.UNCCS.TEST:
eagle/root [/usr/afs/etc] # kvno afs
afs@MSE.UNCCS.TEST: kvno = 4

I then ran:

ktutil> add_entry -password -p afs/cs.unc.edu@MSE.UNCCS.TEST -k 4 -e des-cbc-crc
ktutil> write_kt keytab.ktutil_generated

/usr/sbin/asetkey add 4 keytab.ktutil_generated afs/cs.unc.edu

/etc/init.d/openafs-server restart

I now get the same error as Eric had:

Jan  9 17:14:27 eagle kernel: afs: Tokens for user of AFS id 3903 for cell 
cs.unc.edu are discarded (rxkad error=19270407)

Do I need to map an account like Eric did with the "mapuser" option
to ktpass?

> The key version number must match the number that is actually
> issued by the KDC.  You can identify the version number using
> the MIT Kerberos utility
>   kvno <principal>
>> cell cs.unc.edu are discarded (rxkad error=19270408)
> The OpenAFS translate_et <error_code> command will tell you this
> is because
>   19270408 = ticket contained unknown key version number
>> Windows Event Viewer, System log shows this, sometimes:
>> While processing a TGS request for the target server afs/cs.unc.edu, the
>> account sopko@MSE.UNCCS.TEST did not have a suitable key for generating
>> a Kerberos ticket (the missing key has an ID of 8). The requested etypes
>> were 2.  The accounts available etypes were 3  1.
> What in the world is requesting a ticket with DES-CBC-MD4 ?
>> -----------
>> Once I get Windows AD working can I run both our current kaserver and
>> Windows AD authentication against our production cs.unc.edu openafs cell
>> at the same time? If I can generate afs/cs.unc.edu service pincipals
>> with the same password on the kaserver and the AD server will this work?
>> This may be a good migration path for us. We currently have 2 password
>> databases, kaserver and Windows AD. When we create accounts we use the
>> same user login name for both wndows and linux. Most users keep their
>> passwords the same so logging into Windows gives them an afs token.
>> Even if they don't we just tell them to use their Windows password
>> as we migrate machine configurations.
>> This way we can migrate machines to authenticate to "Windows AD only"
>> over a short period of time and start testing real live systems.
>> First I have to get Windows AD afs service pricnipal working.
> AFS only stores DES keys by key version number.  Ensure that your
> kaserver key and your AD key have different version numbers and
> you will be just fine.
> Jeffrey Altman

John W. Sopko Jr.               University of North Carolina
email: sopko AT cs.unc.edu      Computer Science Dept., CB 3175
Phone: 919-962-1844             Sitterson Hall; Room 044
Fax:   919-962-1799             Chapel Hill, NC 27599-3175