[Rpm-maint] Re: RPM database on NFS root

[Panu Matilainen]

On Sun, 5 Aug 2007, Axel Thimm wrote:

> Hi,
>
> On Sat, Jul 21, 2007 at 07:24:36AM +0000, Panu Matilainen wrote:
>> On Fri, 20 Jul 2007, Mark Hatle wrote:
>>
>>> Jeremy Sanders wrote:
>>>> Are there any plans to be able to host an RPM database over NFS? See
>>>> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=141614
>>>
>>> In my experience (due to NFS locking), it's not possible to do an RPM
>>> database over NFS.  However you do have some options.
>>>
>>>> For our manchines which use remote root over nfs, we use an ext3 filesystem
>>>> mounted over gnbd network block devices to place the rpm database, which
>>>> appears to work (except gnbd is missing from Fedora...) It would be nice
>>>> not to have to do this.
>>>
>>> You can either use sqlite (which is probably a bit slower, and I'm not
>>> sure if it's still available in the rpm-maint 4.4.2.X branch.  It _WAS_
>>> in stock 4.4.2 and the rpm5.org's tree.)  If you go down the route of
>>> the sqlite database, it's still only key/value pair driven, and is much
>>> slower the the berkleyDB interface.  You may also STILL encounter
>>> locking issues w/ sqlite (but in practice I never encountered them...)
>>
>> Sqlite is available in rpm.org tree as well, no intention to remove it.
>
> Is the conversion to sqlite painful, and if not how does one go about
> it? Would it also work on RHEL3,4,5? Is there anyone really running
> any RHEL with sqlite rpmdbs or would I become a guinea pig ;)?

This should give you the idea:
[pmatilai at turre tmp]$ cp -a /var/lib/rpm/ /tmp/rpmdb-sqlite
[pmatilai at turre tmp]$ rm -f /tmp/rpmdb-sqlite/__db.00*
[pmatilai at turre tmp]$ rpm -v --rebuilddbapi 4 --dbpath /tmp/rpmdb-sqlite/ 
--rebuilddb
[pmatilai at turre tmp]$ file rpmdb-sqlite/Packages
rpmdb-sqlite/Packages: SQLite 3.x database
[pmatilai at turre tmp]$ rpm --dbapi 4 --dbpath /tmp/rpmdb-sqlite/ -qa|wc -l
1460

So, it works at least to the point of conversion and queries. I personally 
haven't tested it any further and dunno if people are actually using the 
sqlite db so .. proceed with caution :)

>>> Or you can use RPC for the berkley DB interface.  I don't have details
>>> on this, but this will use a more reliable network interface to go back
>>> to the host for the RPM database access.  This is probably be more
>>> reliable then sqlite.
>>
>> Probably the best available documentation on the subject is here:
>> https://www.redhat.com/archives/rpm-list/2003-May/msg00383.html
>
> Ouch! I don't want a say solaris server having to run rpmdb_svc ... :/

Heh :)

> I think the safest/easiest way to deal with rpmdb over NFS is to pull
> a copy onto a local filesystem before querying.

...and also the fastest way I'd guess.

 	- Panu -