69
IPoIB Setup
About IPoIB
IPoIB (IP over InfiniBand) is simply that: IP packets running over the InfiniBand fabric. This protocol
is useful for testing connectivity into the fabric between two hosts, and also for taking advantage of the
high speed fabric for “legacy” applications that are written to communicate over IP.
The drawback to using IPoIB compared to standard Gigabit Ethernet is that the operating system must
do packet checksumming, whereas modern NIC cards usually offload this function to hardware.
Configuring IPoIB
Configuration of IPoIB is similar to configuring Ethernet interfaces under Linux except the interfaces
are called ib
x
(i.e. ib0, ib1, etc) instead of eth
x
(e.g. eth0, eth1, etc).
To test the IPoIB interfaces, choose a subnet that is currently not routed in your network environment.
For this test, we'll choose 192.168.0.0 with a netmask of 255.255.255.0 and assign “Server 1” the
address 192.168.0.1 and “Server 2” 192.168.0.2.
1. On
Server 1
, use
ifconfig
to configure ib0:
Example
2. Verify that the interface was configured properly:
Example
3. Repeat the process on
Server 2
by configuring ib0 to 192.168.0.2.
If the system failed to configure the interface properly, you may not have successfully installed the
HCA drivers on the operating system. If the drivers did not install, it is likely due to a version
mismatch between the driver suite and the installed kernel.
4. To test connectivity, attempt to ping
Server 2
from
Server 1
, using the
ping
command:
Example
If you do not receive a response from the other server, check cable connectivity. Be sure the
InfiniBand cable is plugged into the correct port for ib0 on the HCA (top port on the PCI adapter
card). Also, check the LEDs on both the HCA and the InfiniBand switch. Refer to
“Interpret HCA
LEDs” on page 63
.
# ifconfig ib0 192.168.0.1 netmask 255.255.255.0
# ifconfig ib0
ib0 Link encap:Ethernet HWaddr 00:00:00:00:00:00
inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST MTU:2044 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:3 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:128
RX bytes:0 (0.0 b) TX bytes:126 (126.0 b)
# ping -c 1 192.168.0.2
PING 192.168.0.2 (192.168.0.2) from 192.168.0.1 : 56(84) bytes of data.
64 bytes from 192.168.0.2: icmp_seq=0 ttl=64 time=154 usec
--- 192.168.0.2 ping statistics ---
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max/mdev = 0.154/0.154/0.154/0.000 ms