/dev/ibd*

The ibd driver implements the IETF IP over Infiniband protocol and provides IPoIB service for all IBA ports present in the system.

The ibd driver is a multi-threaded, loadable, clonable, STREAMS hardware driver supporting the connectionless Data Link Provider Interface, dlpi(7P)). The ibd driver provides basic support for the IBA Unreliable Datagram Queue Pair hardware. Functions include QP initialization, frame transmit and receive, multicast and promiscuous mode support, and statistics reporting.

Use the cloning, character-special device /dev/ibd to access all ibd devices installed within the system.

The ibd driver is dependent on GLD, a loadable kernel module that provides the ibd driver with the DLPI and STREAMS functionality required of a LAN driver. Except as noted in the Application Programming Interface section of this manpage, see gld(7D) for more details on the primitives supported by the driver. The GLD module is located at /kernel/misc/sparcv9/gld on 64 bit systems and at /kernel/misc/gld on 32 bit systems.

The ibd driver expects certain configuration of the IBA fabric prior to operation (which also implies the SM must be active and managing the fabric). Specifically, the IBA multicast group representing the IPv4 limited broadcast address 255.255.255.255 (also defined as broadcast-GID in IETF documents) must be created prior to initializing the device. IBA properties (including mtu, qkey and sl) of this group is used by the driver to create any other IBA multicast group as instructed by higher level (IP) software. The driver probes for the existance of this broadcast-GID during attach(9E).

The values returned by the driver in the DL_INFO_ACK primitive in response to your DL_INFO_REQ are:

This section describes warning messages that might be generated by the driver. Please note that while the format of these messages may be modified in future versions, the same general information will be provided.

While joining IBA multicast groups corresponding to IP multicast groups as part of multicast promiscuous operations as required by IP multicast routers, or as part of running snoop(1M), it is possible that joins to some multicast groups can fail due to inherent resource constraints in the IBA components. In such cases, warning message similar to the following appear in the system log, indicating the interface on which the failure occurred:

NOTICE: ibd0: Could not get list of IBA multicast groups
NOTICE: ibd0: IBA promiscuous mode missed multicast group
NOTICE: ibd0: IBA promiscuous mode missed new multicast gid

Also, if the IBA SM indicates that multicast trap support is suspended or unavailable, the system log contains a message similar to:

NOTICE: ibd0: IBA multicast support degraded due to
unavailability of multicast traps

And when the SM indicates trap support is restored:

NOTICE: ibd0: IBA multicast support restored due to
availability of multicast traps

Additionally, if the IBA link transitions to an unavailable state (that is, the IBA link state becomes "Down," "Initialize" or "Armed") and then becomes active again, the driver tries to rejoin previously joined groups if required. Failure to rejoin multicast groups will trigger messages like:

NOTICE: ibd0: Failure on port up to rejoin multicast gid

If the corresponding HCA port is in the unavailable state defined above when initializing an ibd interface using ifconfig(1M), a message is emitted by the driver:

NOTICE: ibd0: Port is not active

Further, as described above, if the broadcast-GID is not found, or the associated MTU is higher than what the HCA port can support, the following messages are printed to the system log:

NOTICE: ibd0: IPoIB broadcast group absent
NOTICE: ibd0: IPoIB broadcast group MTU 4096 greater than port's
maximum MTU 2048

In all cases of these reported problems when running ifconfig(1M), it should be checked that IBA cabling is intact, an SM is running on the fabric, and the broadcast-GID with appropriate properties has been created in the IBA partition.

The IPoIB service comes preconfigured on all HCA ports in the system. To turn the service off, or back on after turning it off, refer to documentation in cfgadm_ib(1M).

cfgadm(1M), cfgadm_ib(1M), ifconfig(1M), syslogd(1M), gld(7D), ib(7D), kstat(7D), streamio(7I), dlpi(7P), attributes(5), attach(9E)

IBD is a GLD-based driver and provides the statistics described by gld(7D). Note that valid received packets not accepted by any stream (long) will increase when IBD transmits broadcast IP packets. This happens because the infiniband hardware copies and loops back the transmitted broadcast packets to the source. These packets are discarded by GLD and are recorded as 'unknowns'.