I'm looking for recommendations on how to control the startup order of a rack of machine should they all need to be booted back up. In more detail:
Group1: DHCP/DNS/LDAP Server Group2: NFS servers Group3: Web Servers Compute Nodes
I'm currently configuring apcupsd to handle emergency shutdown, particularly for the data servers, but I'm not sure if I should script some complicated startup using WOL, or if there is a early network event system for linux to pause the boot up process until the correct events are received.
If it matters, all the servers are Dell and they have iDRAC, but I haven't been able to get it to work (haven't tried that hard), if that offers any alternatives.