Can I remove the IPC entries in the listener.ora?

[DaPi]

According to the doc, automatic_ipc does nothing from 8.0 onwards.

IPC is only relevent if you have a client process on the server - e.g. an application server running on the same box as the rdbms server and making requests to it. In this case IPC should be more efficient than TCP (fewer layers in the OSI stack).

You should check the tnsnames.ora on the server to see if any services use the IPC protocol - e.g.

HOST =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(Key = V2IPC))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = HST2.WORLD)
    )
  )

If not, you should be able to delete the listener entries (keep a copy of the file before the change ! ! ! !)