Configuration
The An Najah Computing Cluster (ANCC) is designed for high throughput computing. It consists of about 50 worker nodes and 8 data servers. In order to efficiently and reliably manage the system, the provisioning tool Cobbler and the configuration management tool Puppet are used. It is highly recommended to use these tools for all system administration even simple package installation. If these tools are used, commissioning new hosts and consistent management of running hosts, can be achieved with minimal work.
Maintaining Host keys
The ssh host keys are the pub keys for a machine. You can maintain a system wide copy of these keys in the file /etc/ssh/ssh_knownhosts. Maintaining up to date host ssh keys is important for seemlessly managing the system.
There are not scripts in:
/usr/local/adm/puppet/reposity/ssh-hostkeys
That will keep these up to date.
GetHostSshKey hostname - Retrieves the ssh key for hostname and stores it in /usr/local/adm/adm/puppet/repository/ssh-hostkeys/$hostname.key
GenerateSshKnownHosts - Concatenates all the host keys in /usr/local/adm/adm/puppet/repository/ssh-hostkeys/$hostname.key to make /usr/local/adm/puppet/environments/production/modules/localfiles/files/etc/ssh/ssh_known_hosts. This file is then managed by the Puppet module local_files.
The Puppet module local_files will also remove the /root/.ssh/known_hosts
UpdateAllHosts is a cron job file to up date all the ssh host keys on the system. It is run every hour on t3ps.