Fedora Bastion Hosts
background and description of bastion hosts and their unique issues.
There are 2 primary bastion hosts in the iad2 datacenter. One will be active at any given time and the second will be a hot spare, ready to take over. Switching between bastion hosts is currently a manual process that requires changes in ansible.
All of the bastion hosts have an external IP that is mapped into them. The reverse dns for these IPs is controlled by RHIT, so any changes must be carefully coordinated.
The active bastion host performs the following functions:
Outgoing smtp from fedora servers. This includes email aliases, mailing list posts, build and commit notices, mailing list posts, etc.
Incoming smtp from servers in iad2 or on the fedora vpn. Incoming mail directly from the outside is NOT accepted or forwarded.
ssh access to all iad2/vpn connected servers.
openvpn hub. This is the hub that all vpn clients connect to and talk to each other via. Taking down or stopping this service will be a major outage of services as all proxy and app servers use the vpn to talk to each other.
When rebuilding these machines, care must be taken to match up the dns names externally, and to preserve the ssh host keys.