Objective; Replace the current CentOS 5.X distribution and move to the new CentOS 6 Advantages;
- Newer version of packages
- End of life schedule
- Does not require any Xen compatible kernel, paravirt_ops are part of the default kernel
Drawbacks;
- Few
Steps;
- Perform base CentOS 6 setups:
- 1 DomU to test install softwares - can be crashed / reinstalled, will be used to test all newly installed service / RPM
- 1 DomU for 64 bit RPM build - need proper name and clean workflow
- 1 DomU for 32 bit RPM build (optional) - few 32 bit environment
- Search for new sources of RPM or build new RPM for:
- zabbix agent / proxy (validate proper options, use latest stable),
- bacula-client
- common tools (lsof, iftop, dstat, etc.) - get exact list from CentOS 5 kickstart package list
- Rebuild new CNC repo for CentOS 6:
- similar environment and update workflow as currently in place for CentOS 5
- re-add same packages as for CentOS 5 (MySQL, Nginx, Memcache, Varnish, etc.) - get exact list from CentOS 5 auto REPO update (from Alan), define priority for adding them in the auto REPO update (select the most commonly used services first)
- Test all new softwares (in CNC CentOS 6 REPO) on test DomU (created at 1st step), ensure no dependencies are missing
- Test zabbix custom monitoring RPM scripts and ensure all are working and agent is running well
- Update CNC REPO auto update script and Zabbix custom monitoring RPM:
- daily generation of zabbix custom monitoring script should be sent to a regular web folder
- CNC REPO auto update script should check that page and import it in the CNC REPO as any other regular package --> this will ensure we can keep in sync CentOS 5 and CentOS 6 repositories in a unified way
- Update auto install script:
- fork / branch from existing script, or add conditional testing for proper environment
- test auto installation of softwares, fix and update script accordingly if needed
- update auto installation configuration script generation from Build Spreadsheet (Excel Macro):
- ensure the proper CentOS version is taken under account
- add new CentOS version in the spreadsheet if needed
- update spreadsheet template and store / give it back to PM for future setup usage
- Create new Kickstart (netinstall, physical, virtual) - no DomO support
- No need for xen kernel
- LVM should be natively supported by the default CentOS kernel
- Need to get custom softwares in CNC repo for CentOS 6
- test:
- NetInstall physical server setup
- ISO physical server setup
- NetInstall VM server setup
- Final test:
- run NetInstall CentOS 6
- Perform a full Web stack setup; PHP-FPM, Nginx, MySQL, Memcache, monitoring
- validate all is working + perform test QA
Objective; Replace the current Xen 3.3.1 Hypervisor to Xen 4.1.2 Advantages;
- New features available,
- Better performance and memory management,
- Better support from the community, 3.3.1 is several years old and not mentioned much in tutorials anymore.
Drawbacks;
- CentOS 6 doesn't support Xen anymore and require custom build Linux kernel and Hypervisor
Solution;
- Use CentOS 5.8 for now; we rarely upgrade DomO and they usually are not publicly reachable, we don't need newer softwares as we would for the DomU
Steps;
- Search publicly available REPO that holds