kdb5_util-1.15.1: Invalid argument while making newly loaded database live

[Ken Hornstein]

>We have a setup where the kerberos database (db2) is hosted on an NFS
>server. There are multiple KDC servers each mounting the NFS share and
>serving traffic.

I have to say up front that it is generally agreed that putting any database
file on a NFS filesystem is a bad idea.  Also, it kind of sounds like
your multiple KDCs are serving the SAME database file?  If so, THAT is
a huge problem!

>>kdb5_util: Cannot open DB2 database
>'/var/kerberos/krb5kdc_shared/principal~': Invalid >argument while deleting
>bad database /var/kerberos/krb5kdc_shared/principal

I am looking at newer Kerberos code, so perhaps this has changed, but
that error comes from krb5_db_destroy() failing.  For DB2, that ends
up calling krb5_db2_destroy().  That function does a lot of things,
and it's hard at a glance to figure out which part of it is failing; I
suspect the only way to figure out what is going wrong there is to build
a version of Kerberos with full debugging symbols and set a breakpoint
on krb5_db2_destroy().  I have a strong suspicion that the database file
is getting corrupted in a such a way that the other routines cannot
recover, and that's likely due to the use of NFS (especially if multiple
KDCs are using the same database file).

--Ken