[Samba] Cannot create keytab for Apache Kerberos auth: Client SPN_RECORD not found in Kerberos database while getting initial credentials

[Lorenzo Milesi]

> kinit: Client 'HTTP/test2021.ufficyo.com at AD.INTERNAL.CONTOSO.COM' not found in
> Kerberos database while getting initial credentials

The problem seems to be in how Samba stores userPrincipalName.

Bug #9113 [1] has the solution (or probably a workaround):
> If I change 'userPrincipalName' in Samba 4 via ldbedit to the value of 'servicePrincipalName' + REALM, then kinit works. 

And indeed updating the attribute finally made kinit work!

I suppose this means there must be a single account for each service, while SPN is supposed to authenticate several services with a single account. I wonder how it behaves with CNAME hosts.

I also found a last year thread [2] on this ml reporting a possible bug on how searches are performed for SPN entries, but coulnd't find a corresponding bugzilla entry for it.

[1] https://bugzilla.samba.org/show_bug.cgi?id=9113
[2] https://lists.samba.org/archive/samba/2020-June/230197.html
-- 
Lorenzo Milesi - lorenzo.milesi at yetopen.com 
CTO @ YetOpen Srl

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