The Rocks database holds information that has been discovered about a host and in particular records network interface information including MAC addresses and local device modules. The Rocks command line has several tools to inspect and update entries in the database. Reinstallation of a node will apply the changes to a node. See the following section on Swapping Frontend Ethernet Interfaces.
For the following discussion, a frontend named "jeebs" will be used for illustation. To list the ethernet interfaces do the following:
# rocks list host interface jeebs SUBNET IFACE MAC IP NETMASK MODULE NAME VLAN private eth0 00:0e:0c:a7:57:d7 10.1.1.1 255.0.0.0 e1000 jeebs ------ public eth1 00:19:b9:21:b8:b6 172.19.119.241 255.255.255.0 tg3 jeebs.rocksclusters.org ------
This describes the two interfaces, eth0 and eth1. Suppose that it is desired to swap these two interfaces. That is we would want to associate the mac address 00:0e:0c:a7:57:d7 with eth1. To do this we must also associate the correct module. The following will change the information only in the database. This uses the rocks set host interface group of commands.
# rocks set host interface mac jeebs iface=eth1 mac=00:0e:0c:a7:57:d7 # rocks set host interface module jeebs iface=eth1 module=e1000 # rocks set host interface mac jeebs iface=eth0 mac=00:19:b9:21:b8:b6 # rocks set host interface module jeebs iface=eth0 module=tg3
Then the updated database configuration is as follows
# rocks list host interface jeebs SUBNET IFACE MAC IP NETMASK MODULE NAME VLAN private eth0 00:19:b9:21:b8:b6 10.1.1.1 255.0.0.0 tg3 jeebs ------ public eth1 00:0e:0c:a7:57:d7 172.19.119.241 255.255.255.0 e1000 jeebs.rocksclusters.org ------
To apply the changes to the frontend, execute:
# rocks sync config # rocks sync host network localhost
The above commands will update some configuration files on the frontend (e.g., /etc/sysconfig/network-scripts/ifcfg-*), then restart the frontend's network.