3.12.2 Changing the IPoIB mode of an InfiniBand Interface

The IPoIB driver supports the use of either connected mode or datagram mode with an interface, where datagram mode is the default mode. Changing the mode of an InfiniBand interface by echoing either connected or datagram to /sys/class/net/ibN/mode is not supported for UEK R3. It is also not possible to change the mode of an InfiniBand interface while it is enabled if you are running UEK R3.

To change the IPoIB mode of an InfiniBand interface on a UEK R3 system:

  1. Edit the /etc/sysconfig/network-scripts/ifcfg-ibN configuration file, where N is the number of the interface:

    • To configure connected mode, specify CONNECTED_MODE=yes in the file.

    • To configure datagram mode, either specify CONNECTED_MODE=no in the file or do not specify this setting at all (datagram mode is enabled by default).


    Before saving your changes, make sure that you have not specified more than one setting for CONNECTED_MODE in the file.

  2. To enable the specified mode on the interface, use the following commands to take down the interface and bring it back up:

    # ifdown ibN
    # ifup ibN


This issue is resolved in UEK R4.

(Bug ID 17479833)