add centos 7.x version update process and nss instructions

docs/distributions/cc7.md

@@ -166,3 +166,77 @@ Sync web page to production site [linux.web.cern.ch/linux](https://linux.web.cer
 Double check the rendering looks fine
 
 Finally go back to your terminal that is still running the bsmailusers process and confirm 'yes' to send to send the mail.
+
+## 'Minor' (7.x -> 7.x+1) version release process.
+
+### Introduction
+
+This documentation describes the steps needed to promote an upstream point release
+
+CentOS typically releases the new version ~40 days after the RHEL release. The process CentOS follows is to first release new binary packages into the continuous release (CR) repository. This allows the community to test the upgrade process before they are promoted to GA and binary ISO images are built and published.
+
+The CERN process is similar to the standard release process, making the upstream packages in CR available for CC7. The CERN CR repository is enabled by default on all 'QA' nodes, thus we have a fleet of machines that will upgrade/distrosync to the new packages.
+
+### Release process
+
+Once CR is available, the steps to facilitate the new release are:
+
+* Create /mnt/data{1,2}/dist/cern/centos/7.$release.$yearmonth/{os,cr,cr-testing} directories
+* Symlink /mnt/data{1,2}/dist/cern/centos/7.$release.$yearmonth to /mnt/data{1,2}/dist/cern/centos/7.$release
+* Symlink /mnt/data{1,2)/dist/cern/centos/7.1.1503/{centosplus,centosplus-testing,cern,cern-testing,cernonly,cernonly-testing,cloud,cloud-testing,extras,extras-testing,fasttrack,fasttrack-testing,rhcommon,rhcommon-testing,rt,rt-testing,sclo,sclo-testing,storage,storage-testing,updates,updates-testing,virt,virt-testing} to /mnt/data{1,2}/dist/cern/centos/7.$release.$yearmonth/
+* Download cr from 'upstream': `bscentos2test -d "cc7" -r cr`
+* Rebuild the kernel (and potentially nss, see 'Miscellaneous' for details): `bsbuildmodules`
+* Move CERN built packages: `bsbuild2test -d cc7 -r cr`
+* Create cr-testing repodata: `bsregenrepos -d cc7 -r cr-testing`
+* Sync to data1/eos: `bssync -t "data1 eos" -d cc7 -r cr-testing`
+* Perform testing on a VM with `yum --enablerepo=cr-testing update`
+* Promote cr-testing to cr `bstest2prod -d cc7 -r cr`
+* Regen repodata `bsregenrepos -d cc7 -r "cr cr-testing"`
+* Sync to data1/eos `bssync -d cc7 -r "cr cr-testing" -t "data1 eos"`
+* Test the upgrade process on several VMs `yum --enablerepo=cr update`
+* Send email template to users informing that CentOS7.$release is available for testing. The recipient should be 'linux-users@cern.ch' and the following recipients should be included in BCC 'linux-announce@cern.ch', 'linux-announce-test@cern.ch', 'ai-admins@cern.ch'
+
+```
+From: Ben Morrice
+Sent: 03 September 2019 14:58
+To: linux-users (Forum for Linux related information exchange at CERN.)
+Subject: CERN CentOS 7.7 testing available.
+
+Dear Linux users.
+
+We are pleased to announce the updated CERN CentOS Linux (CC7) TEST version:
+
+             *******************************
+             CC 7.7 is available for testing
+             *******************************
+                as of Tuesday 03.09.2019.
+
+For information about CC7, including installation instructions please visit:
+
+         http://cern.ch/linux/centos7/
+
+Please note that install media is not yet available.
+We will send an additional email when ready.
+
+* Updating CERN CentOS 7.6 to 7.7
+
+CC7 system can be updated by running:
+
+# yum --enablerepo=cr \
+  --enablerepo={updates,extras,cern}-testing \
+  --enablerepo=epel-testing \
+  clean all
+
+# yum --enablerepo=cr \
+  --enablerepo={updates,extras,cern}-testing \
+  --enablerepo=epel-testing \
+  update
+
+* Agile infrastructure
+
+As a reminder, all puppet configured machines within the
+QA environment will receive automatically those updates.
+
+--
+Ben Morrice for Linux.Support@cern.ch
+```

[Ghost User]

just a question. GA or QA? If GA, what does it stand for?

[Ben Morrice]

general availability