Setting up CTDB on OCFS2 and VMs ...

[Stefan Kania]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi Michael, hi Rowland,
Am 12.12.2014 um 21:52 schrieb Michael Adam:
> Hi Rowland,
> 
> I am really sorry that you are frustrated. Pleas keep on!
> 
> We do try to document stuff, but clusters with ctdb is still an
> area that is not done by the average admin. And there are not so
> many people working on the code, so as usual, documentation sadly
> lacks behind.
> 
I'm on the way writing a documentation for ADMINS ;-). As soon as I
finished withe te german version (that will be if everything is
working) I will translate it. Rowland, if you want, I can send you my
german documentation if you want, at least you can get all the
commands and config-file information out of it.

> Someone like you, who with the help of us devs finally gets to a
> working system, might help us in the end to improve the docs! :-)
> 
That's what I want.
> Clustering also relies on a whole additional area which is the
> corresponding cluster file systems used underneath, which makes it
> difficult to have comprehensive documentation for a concrete
> setup.
> 
That wat I'm fighting with, no documentation or only
developers-klingon-language ;-)
> That being said, there is documentation out there, but not
> necessarily terribly up to date, and not precisely what you want.
> 
> On the samba wiki, there is the generic but somewhat superficial
> 
> https://wiki.samba.org/index.php/CTDB_Setup
> 
> and as a specific example the GFS/CTDB/Samba howto:
> 
> https://wiki.samba.org/index.php/GFS_CTDB_HowTo
> 
> which is of course redhat-cluster/gfs specific as far as the file
> system is concerned.
> 
> The manual pages of ctdb are also pretty good by now!
> 
That' right, BUT the wiki not mentions how to get the cluster into a
samba4 domain and how permissions work on a cluster-fs
> It is true that Debian is especially rare in these clustered Samba
> docs. This is due to the fact, that for a long time, there was no 
> big focus on cluster file systems in Debian.
> 
> A couple of years ago, I have given a couple of talks and courses
> about clustered Samba partly also using Debian and Gluster, but
> also RedHat and GFS. My 2010 notes
> 
> http://www.samba.org/~obnox/presentations/sambaXP-2010/sambaxp-2010-tutorial-ctdb-handout.pdf
>
>  even contain some note on what is different and needs to be
> considered on a Debian systems. (The main difference is that
> /etc/default is used instead of /etc/sysconfig by most packages.)
> 
> At that time, OCFS2 was not yet ready for CTDB/Samba, and GlusterFS
> was mainly available in Debian, but did not perform very well. Now
> Gluster has been taken on by RedHat, and I think we can expect
> updates from that corner in the nearer future.
> 
> Here is a paper explaining some of the fundamentals of CTDB and the
> basic configuration of CTDB and clustered samba on Top.
> 
> http://www.samba.org/~obnox/presentations/sambaXP-2009/samba-and-ctdb.pdf
>
>  And a pretty similar article from Linux Magazine:
> 
> http://www.linux-magazine.com/Issues/2009/105/Samba-for-Clusters
> 
> and an accompanying one on registry configuration:
> 
> http://www.linux-magazine.com/Issues/2009/105/Samba-s-Registry
> 
> Some of the details need to be checked because the info is 4-5
> years old, but the basics are still correct.
> 
> As a last but possibly important remark (for those who have not
> fallen asleep by now ;-) let me mention that as far as I know,
> Stefan Kania (whom I have copied in this reply, since I am not 
> certain that he is subscribed to the list) is currently working on
> a reproducible setup with Debian/Gluster/CTDB/Samba. Maybe he can
> give some insight on the specialities of a CTDB setup on current
> Debian.
> 
I'm reading the samba-mailinglist. Is there another one?

> 
> I apologize for having pointed mainly to my own writings, but at
> the time I have undertaken some considerable efforts to create some
> documentation and explanations, so I hope this is of any use. :-)
> 
Regards

Stefan

> Cheers - Michael
> 
> PS: Also, you are asking why Ronnie suggests a single node 
> cluster. Because it is always good to start out with a simple
> case. And once you mastered that, move on to more complicated
> things. And you can even see most config points in that 1-node
> cluster.
> 
> 
> On 2014-12-12 at 10:36 +0000, Rowland Penny wrote:
>> On 11/12/14 18:32, ronnie sahlberg wrote:
>>> I just tried building a single-node "cluster" on debian with
>>> ctdb.
>> 
>> Why a single node ????
>> 
>>> I can check building a 4 node cluster next week when I am home
>>> from my travels.
>> 
>> Try it with two nodes
>> 
>>> 
>>> To get ctdb running on ubuntu 14.10, as root:
>> 
>> Hang on, you said 'debian' above
>> 
>>> 
>>> 1, Install the ctdb package: apt-get install ctdb
>>> 
>>> 2, create a missing directory mkdir -p /var/lib/run/ctdb
>> 
>> Why is there a missing directory, sounds like a bug to me.
>> 
>>> 
>>> 3, remove the reclock file vi /etc/default/ctdb and comment out
>>> CTDB_RECOVERY_LOCK
>> 
>> But I want the lock.
>> 
>>> 4, create a nodes file vi /etc/ctdb/nodes and add the line
>>> 127.0.0.1
>> 
>> Yes, but why '127.0.0.1' ???
>> 
>>> 
>>> 5, create a public addresses file vi
>>> /etc/ctdb/public_addresses and add the two lines 127.0.0.2/8
>>> lo 127.0.0.3/8 lo
>> 
>> Do you have to create these ipaddresses, if so where and how
>> 
>>> 6, start ctdb service ctdb start
>>> 
>> 
>> That is this first part I really understood.
>> 
>>> then check everything looks fine with 'ctbb status' and 'tail 
>>> /var/log/ctdb/log.ctdb'
>>> 
>>> 
>>> That will not really create a very interesting cluster, just
>>> one node, two public addresses and all on loopback. But this
>>> should at least verify that ctdbd will start and run. Then you
>>> can just shut it down and edit /etc/ctdb/nodes|public_addresses
>>> and make them more interesting.
>> 
>> Again, why just one node. ??
>> 
>>> I personally suggest never running anything smaller than 4
>>> node clusters for real data.
>> 
>> Yes, but I am testing, so where is the documentation for people
>> like me, who just want to get a couple of nodes up and running
>> ???
>> 
>> Rowland
>> 
>>> 
>>> Please see man ctdb man ctdbd less /etc/default/ctdb 
>>> http://ctdb.samba.org/configuring.html
>>> 
>>> it should contain most to get started with ctdb.
>>> 
>>> 
>>> regards ronnie sahlberg.
>>> 
>>> 
>>> 


- -- 
Stefan Kania
Landweg 13
25693 St. Michaelisdonn


Signieren jeder E-Mail hilft Spam zu reduzieren. Signieren Sie ihre
E-Mail. Weiter Informationen unter http://www.gnupg.org

Mein Schlüssel liegt auf

hkp://subkeys.pgp.net

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1

iEYEARECAAYFAlSMJ2sACgkQ2JOGcNAHDTbBfACgi0Wn0u+bFSX77d3z8mEMvfsa
3t8AoNPf2iOxtCV5NtywkPvox4WxAKnk
=ND74
-----END PGP SIGNATURE-----