42 SunFDDI/P1.0 Adapter User’s Guide—May 1997
5
The local station cannot reach FDDI stations located
on a remote Ethernet network. Check that the IP address and host name of the remotestation
is entered in the NIS map or NIS+ tables (or in /etc/hosts
on each remote station if you are not runningNIS or NIS+).
If you are operating in a Solaris 2.xenvironment,which uses
MTU path discovery,check that packets are being transmitted
across the bridge between the networks. Many bridges do not
yet support MTU path discovery and do not fragment the
large packets sent by the FDDI stations. In this case you may
need to disable this feature on your station by typing:
#ndd —set /dev/ip ip_path_mtu_discovery 0
Check that the routing tables areusing netstat —r. Check
foran pf interface that shows a route to a gateway with the UG
flags set. If you can reach the local gateway,then the problem
probably lies with the IP routing.
Tryto confirm that the remote station is configured and
running, and if possible try to reach the local station fromthe
remote station. If you can, it indicates that the problemlies
with the local IP routing.
Tryto reach the router nearest the remote station. If you can, it
indicates that the fault lies between the remote station and the
router.If you cannot, try to reach a router that is closer to the
local station. Continue in this way until you have isolated the
router that is droppingor misrouting packets.
If the dynamic routing protocolis not adding routes, try
adding a static route to the remotestation. This method is not
recommended for largenetworks with a large number of
nodes.
Running pf_stat with the —m option (to display
information about the neighboring stations) shows
frequent error frames and lost frames.
This could indicate a noisy network. For fiber connections,
noise is probably caused by dirt or greaseon the optical
surface or by a damaged cable. Unshielded twisted-pair is
sensitive to electrical and electromagnetic interference.Note
that the receipt of error frames and lost frames does not
give any indication of where the problemis occurring on the
ring.
Table5-2 Problems Running SunFDDI/P (Continued)
Problem Action