[CentOS-mirror] Mirror Changes - Important

Lance Davis lance at uklinux.net
Wed Mar 30 20:42:11 UTC 2005

Due to the split of mirrors with cAos , it will be necessary for mirrors 
to make some changes to the way that they mirror the CentOS tree, as 
moving forward it will no longer be a part of the caosity tree.

Firstly mirrors need to decide whether they are mirroring CentOS or cAos 
or both. They are distinct operating systems, CentOS is a rebuild of 
Enterprise Linux , whereas cAos is an rpm based distribution in its own 

For more information see www.centos.org or caos.caosity.org

At present both trees are mirrored with a single rsync of 
mirror.caosity.org::cAos - moving forward two rsyncs will be needed :-

mirror.caosity.org::caosity that will get the caos tree


msync.centos.org::CentOS that will get the CentOS tree

Please note that at present CentOS will be listed and stored within the 
cAos tree, this should not be the case in the future - CentOS should never 
be stored or listed as a part of cAos or caosity.

Mirror Changes

In order to achieve the changes required with minimum download bandwidth 
the following steps should be carried out. (Note that individual 
circumstances may vary - if in doubt do nothing and ask) .

1. Stop cron based rsync job from syncing

2. Move the CentOS tree to its new location, which should be at the root 
   of the publically served tree. 

   This can either be achieved with 'mv' or if you want a 2nd chance at it 
   'cp -al' which will create a hardlinked copy of the tree (as long as it 
   is on the same partition)

   eg with directory structure 	/pub

   cp -al /pub/caos/centos /pub/
   mv /pub/caos/centos /pub

   to end up with 		/pub/
   (and 			/pub/caos/centos/ if using cp -al)

3. Create a new rsync cron job to sync the CentOS tree (if required) . 
This should be    something like :-

   rsync -aqzH --delete msync.centos.org::CentOS /pub/

   *** note the change to msync.centos.org *** mirror.centos.org is 
   deprecated for rsync use - to allow us to use different servers for yum 

   please use rsync -anvzH --delete msync.centos.org::CentOS /pub/ 
   first to test that the command will do the right thing ('n' is dry run 
   and will just show what wil be transferred - which in theory should be very 
   little - if it says 40 GB + then the command is wrong !!)

Note that due to the way that rsync works any updates will only be written 
to this new tree and not the hardlinked tree left behind if using cp -al 
above ( that can be deleted once you are happy with the new location 

4. Create a new rsync cron job to sync the cAos tree (if required). This 
should be something like :-

   rsync -aqzH --delete mirror.caosity.org::caosity /pub/

   *** note the change to ::caosity - ::cAos will still sync both trees 
       for mirrors that havent restructured yet.                       ***

   This will also delete the CentOS tree left underneath the caos tree 

You should now have both trees in the correct places.

5. Please email the list to say that you have restructured your mirror and 
what the new urls will be for public use. We will update the databases to 
reflect these new locations.

6. It is not necessary to mirror all of centos if you do not wish to - eg 
you can choose whether to carry 2.1 , 3.3, 3.4, 4.0 - but please note in 
the email any trees that you will not be carrying and we will note that in 
the database.

7. In the very near future we will be restricting access to 
msync.centos.org to publically listed mirrors only - we have to establiush 
a way for new mirrors to sync first though.

8. We will be tracking which mirrors have/havent restructured and will 
contact individual mirrors accordingly.

 There is now an irc channel - #centos-mirror 
on irc.freenode.net where mirroring discussions may be held.


uklinux.net - 
The ISP of choice for the discerning Linux user. 

More information about the CentOS-mirror mailing list