Please somebody help me on this if anybody has done this activity on Exadata.
Hi Avadhut -
What networks on the Exadata are you needing to change the netmask for? I have never changed a netmask on Exadata. However, if I were to do so I would follow the instructions in MOS Note "Changing IP addresses on Exadata Database Machine (Doc ID 1317159.1)" - but obviously only modify the areas specific to the netmask, which should mean less changes than if changing IP address but still should cover all the components needed for each of the various networks, switches, and other configuration files. You should also refer to, as does this MOS note, ch.6 of the Exadata Machine Owners Guide... the first few sections of this guide covers the networking configuration on Exadata. You may also need to refer to ch.7 of the Owners Guide on Maintainin the Exadata Rack... there are several sections on making various updates to the networking components on Exadata - lots of information specific to maintenance and changing the Infiniband network information.
Hope that helps.