Information Technology Reference
In-Depth Information
Table12-3 ISO CLNS: Host Cannot Access Hosts on Local or Remote Network (continued)
Possible Problem
Solution
Level 1 router or
ES has bad
address
Verify that the Level 1 router has the same address as the ES.
1.
Verify that all bytes of the NSAP
4
address, up to but not
including the system ID, are the same on both the router and
the ES. The domain and area addresses must match, and the
station IDs must be unique. (The value of the n-selector byte
has no impact in this case.)
2.
ES host is not
running ES-IS
5
protocol
1.
Use the appropriate host commands to verify that an ES-IS
process is running. If necessary, initiate the ES-IS process on
the host.
2.
Check the adjacency database on the host and verify that it
has an entry for its directly connected router.
3.
Use the
debug clns packet
privileged exec command on the
Level 1 router to verify that it sees and forwards packets
from the ES.
Caution: Because debugging output is assigned high priority in
the CPU process, it can render the system unusable. For this
reason, use debug commands only to troubleshoot specific
problems or during troubleshooting sessions with Cisco
technical support staff. Moreover, it is best to use debug
commands during periods of lower network traffic and fewer
users. Debugging during these periods decreases the likelihood
that increased
debug
command processing overhead will affect
system use.
4.
If necessary, statically configure the router to recognize the
ES by using the
clns es-neighbor
interface configuration
command. The following is the syntax for the
clns
es-neighbor
command:
clns es-neighbor
nsap snpa
Syntax Description:
•
nsap—
Specific NSAP to map to a specific MAC
6
address.
•
snpa—
Data link (MAC) address.
Example:
The following example defines an ES neighbor on Ethernet
interface 0:
interface ethernet 0
clns es-neighbor
47.0004.004D.0055.0000.0C00.A45B.00 0000.0C00.A45B
In this case, the end systems with the following NSAP, or NET,
7
are configured with an Ethernet MAC address of
0000.0C00.A45B:
•
47.0004.004D.0055.0000.0C00.A45B.00
continues
