Custom YUM repositories for the Tier3

Introduction

PSI runs a customized version of Scientific Linux + some local RPMs repositories ( e.g. including IBM GPFS ) ; the T3 uses these PSI repositories but it also has its own YUM repositories organized by SL version:

• /afs/psi.ch/software/linux/dist/scientific/57/Tier3/
• /afs/psi.ch/software/linux/dist/scientific/6/Tier3

M. Gasser commented in this way our request to create our own YUM repositories:

Hi Fabio,

Go-to /afs/psi.ch/software/linux/dist/scientific/57/
There, you create a directory such as tier3 (not in the psi subdirectory).  We use so called all subdirectories to put all versions of an RPM in.
From there we just take the latest ones and put corresponding symlinks to snapshot directories, the date of creation is the name of such a
snapshot. I distinguish between unstable, testing and stable, this is quite handy, because when I try new things, I can point unstable to another snapshot as testing or stable.
However, it's up to you.  To populate your repo you just can copy things or you can use 'repomanage' (package yum-utils, 
see /afs/psi.ch/software/linux/dist/scientific/57/scripts/create_new_snapshots.sh or the manpage for an example how to use it).

When your repo is populated, you have to run the command 'createrepo' (package createrepo), 
for instance in the directory you have the latest RPMS which you wanna install. The subdirectory repodata is made, where
the metadata of your RPMS are kept. On the client you have to edit /etc/yum.conf accordingly, to address this repo, or you add a separate repo config
file to /etc/yum.repos.d/ (see the existing yum.conf as an example).

Important, each time you change something in your repo you have to run createrepo again, even if you copy the same RPM again to the same place,
otherwise you'll get an error on the client. On the client it's often a good idea to 'yum clean all' to clear the yum cache, before running
yum install or whatever. So you are sure the repo data on your client corresponds to the latest repo data in your repo.
>
> Hi Marc
>
> could you please create, or tell me how to, a directory like:
> /afs/psi.ch/software/linux/dist/scientific/57/psi/Tier3
>
> Fabio

to do what Marc said we need this RPM:

Installed Packages
Name       : createrepo
Arch       : noarch
Version    : 0.4.11
Release    : 3.el5
Size       : 216 k
Repo       : installed
Summary    : Creates a common metadata repository
URL        : http://linux.duke.edu/projects/metadata/
License    : GPLv2
Description: This utility will generate a common metadata repository from a directory of
           : rpm packages

HTTP protection of the YUM repository

Be aware of the htaccess-special.acl files, they prevent Internet access to the PSI yum repositories:

[martinelli_f@t3ui02 scientific]$ cat /afs/psi.ch/software/linux/dist/scientific/57/htaccess-special.acl 
####################################################################
#
# PSI SLP REPO ACCESS
#
####################################################################

Order deny,allow
  deny from all
  allow from 129.129 10.1.1.0/24 172.16.0.0/12 192.33.120 192.33.121 192.33.123 192.33.126 192.168.6 192.33.118 192.33.127

[martinelli_f@t3ui02 scientific]$ cat /afs/psi.ch/software/linux/dist/scientific/6/htaccess-special.acl 
####################################################################
#
# PSI SLP REPO ACCESS
#
####################################################################

Order deny,allow
  deny from all
  allow from 129.129 10.1.1.0/24 172.16.0.0/12 192.33.120 192.33.121 192.33.123 192.33.126 192.33.127 192.168.6 192.33.118 195.176.0 

YUM pointer files

Usually Puppet will take care of this file

SL5

On the SL5 servers where you want to deploy our own T3 RPMs it must to be present this YUM pointer:

# https://wiki.chipp.ch/twiki/bin/view/CmsTier3/PSIYumRepositoryForTier3
[Tier3]
name=Tier3 repo
baseurl=http://linux.web.psi.ch/dist/scientific/57/Tier3/stable
enabled=1
gpgcheck=0
# top priority
priority=1

SL6

The equivalent YUM pointer for SL6 is:

[root@t3fs13 ~]# cat /etc/yum.repos.d/Tier3.repo 
# Puppet Managed File
# 
# https://wiki.chipp.ch/twiki/bin/view/CmsTier3/PSIYumRepositoryForTier3
[Tier3]
name=Tier3 repo
baseurl=http://linux.web.psi.ch/dist/scientific/6/Tier3/stable
enabled=1
gpgcheck=0
# top priority
priority=1

How to add new RPMs into the YUM repository

To add a new RPM(s) in our YUM repository you have to:

• login into a t3ui* server
• run klog to create a Kerbers ticket
• copy the new RPM(s) into /afs/psi.ch/software/linux/dist/scientific/57/Tier3/all or /afs/psi.ch/software/linux/dist/scientific/6/Tier3
• cd /afs/psi.ch/software/linux/dist/scientific/57/scripts or cd /afs/psi.ch/software/linux/dist/scientific/6/scripts
• Create a new snapshot by running: ./create_new_snapshots.sh Tier3
• Update the testing/stable symbolic links; probably just testing since stable points to testing

Example:

[martinelli_f@t3ui03 scripts]$ ./create_new_snapshots.sh Tier3
### begin ./create_new_snapshots.sh ###
Sourcing configuration file /scripts/dist-config
Running ./create_new_snapshots.sh, this will take some time ...
ALL_DIRS is psi others update.i386 update.x86_64 epelp dagp nagios nonfree cluster fastbugs.i386 fastbugs.x86_64
The following directories will be processed:
### Tier3
Create snapshot for Tier3 ...
creating directory /afs/psi.ch/software/linux/dist/scientific/57/Tier3/20111219/ ...
------------------------------------------------------------------------
Using /afs/psi.ch/software/linux/dist/scientific/57/Tier3/all 
to populate /afs/psi.ch/software/linux/dist/scientific/57/Tier3/20111219 ...
(all RPMS will be copied as soft links)
------------------------------------------------------------------------

Find newest rpms, please wait ... done.
Create softlinks for each ../all/TARGET.rpm in /afs/psi.ch/software/linux/dist/scientific/57/Tier3/20111219/: 
  ganglia-3.0.7-1.src.rpm
  ganglia-devel-3.0.7-1.x86_64.rpm
  ganglia-gmetad-3.0.7-1.x86_64.rpm
  ganglia-gmond-3.0.7-1.x86_64.rpm
  ganglia-web-3.0.7-1.noarch.rpm
  quota-3.17-1.2.5.x86_64.rpm
  sun-sge-bin-linux24-x64-6.2-5.x86_64.rpm
  sun-sge-common-6.2-5.noarch.rpm
done.

Run createrepo in /afs/psi.ch/software/linux/dist/scientific/57/Tier3/20111219/ ...
8/8 - sun-sge-common-6.2-5.noarch.rpm                                           
Saving Primary metadata
Saving file lists metadata
Saving other metadata
done.

### end ./create_new_snapshots.sh ###
[martinelli_f@t3ui03 scripts]$

Like showed above, the Marc's create_new_snapshots.sh script creates a new repository, in this case 20111219 ; to use it you need to change the testing/stable soft link:

[martinelli_f@t3ui02 Tier3]$ pwd
/afs/psi.ch/software/linux/dist/scientific/57/Tier3
[martinelli_f@t3ui02 Tier3]$  ll
total 10
drwxr-xr-x 3 martinelli_f cms 2048 Dec 14 11:19 20111214
drwxr-xr-x 3 martinelli_f cms 2048 Dec 14 11:54 20111214-1154
drwxr-xr-x 3 martinelli_f cms 2048 Dec 19 17:21 20111219
drwxr-xr-x 3 martinelli_f cms 2048 Dec 20 12:27 all
lrwxr-xr-x 1 martinelli_f cms    3 Dec 14 12:01 testing -> 20111214
[martinelli_f@t3ui02 Tier3]$ rm -f testing && ln -s 20111219 testing
[martinelli_f@t3ui02 Tier3]$ ll
total 10
drwxr-xr-x 3 martinelli_f cms 2048 Dec 14 11:19 20111214
drwxr-xr-x 3 martinelli_f cms 2048 Dec 14 11:54 20111214-1154
drwxr-xr-x 3 martinelli_f cms 2048 Dec 19 17:21 20111219
drwxr-xr-x 3 martinelli_f cms 2048 Dec 20 12:27 all
-rw-r--r-- 1 martinelli_f cms  503 Dec 14 12:08 htaccess-intranet.acl
lrwxr-xr-x 1 martinelli_f cms    8 Dec 20 12:38 testing -> 20111219

Basically case by case, and server by server, you have to decide if to use a new soft link or to recycle a past one. Common case is 2 soft links testing newer, or the same, than stable and the development servers pointing to testing while the production servers pointing to stable.

How to install an RPM from the YUM repository

If the YUM pointer file is properly configured as well as the soft link on the /afs/ filesystem then you simply execute yum like in the following example ( we're installing a custom quota RPM that understands ldaps ):

[root@t3vmui01 ~]# yum install quota
Loaded plugins: kernel-module
Excluding Packages from 54 update
Finished
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package quota.x86_64 1:3.17-1.2.5 set to be updated
--> Finished Dependency Resolution
Beginning Kernel Module Plugin
Finished Kernel Module Plugin

Dependencies Resolved

===========================================================================================================================================================================
 Package                                Arch                                    Version                                       Repository                              Size
===========================================================================================================================================================================
Installing:
 quota                                  x86_64                                  1:3.17-1.2.5                                  Tier3                                  358 k

Transaction Summary
===========================================================================================================================================================================
Install      1 Package(s)         
Update       0 Package(s)         
Remove       0 Package(s)         

Total download size: 358 k
Is this ok [y/N]: y
Downloading Packages:
quota-3.17-1.2.5.x86_64.rpm                                                                                                                         | 358 kB     00:00     
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing     : quota                                                                                                                                               1/1 

Installed:
  quota.x86_64 1:3.17-1.2.5                                                                                                                                                

Complete!
[root@t3vmui01 ~]#

How to consolidate the YUM repository

I discourage this step If you feel confident about the stability of the T3 RPM(s) you can apply the createrepo command directly to the all subdirectory, but it's usually safer to work by using the nice snapshots mechanisms suggested by Marc.