Hitachi GR2000 Series - Manual (Page 191)

Troubleshooting
GR2K-GA-0015 7-25
Ver. 07-02
Step 3. Date and time when the errors occur are displayed in log messages. Check
whether a log message is displayed for the date/time when the
communication error occurred.
Step 4. For details about the log message contents displayed for the date/time
when the communication error occurred, see “Log Message and MIB
Reference”.
Step 5. If a log message does not exist for the date/time when the communication
error occurred, go to the next step of the troubleshooting flowchart (Figure
7-6).
7.5.1.2 Inspection of Interface Status
Even if the own router operates properly, adjacent hardware may fail. The procedure
for checking the interface status between this router and neighbor devices (hosts/
routers) is shown below:
Step 1. Log in to the own router from the device management terminal.
Step 2. Check Up/Down status of the interface with applicable devices by using the
show ip interface command.
Step 3. When the applicable interface is in Down status, see Section 7.4,
“Communication failure in network interface”.
Step 4. When the applicable interface is in Up status, go to Subsection 7.5.1.3,
“Determination of Failure Range (Echo Test from Own Router)”.
7.5.1.3 Determination of Failure Range (Echo Test from Own Router)
When no failure is found in the own router, a failure may exist somewhere in the
route between this router and the destination. The procedure to determine the failure
range is as follows.
Step 1. Log in to the own router from the device management terminal.
Step 2. Use the ping command to check accessibility with relevant devices on the
route where the communication failed. See Subsection 5.2.2, “Confirming
the communication with relevant destination address” for an example of
ping operation and how to read the execution result.
Step 3. When communication to the destination turns out to be missing with the
ping command, use ping on the neighbor device to see if communication to
the destination is available.
Step 4. As a result of ping command execution, go to Subsection 7.5.1.5,
“Inspection of ARP Information with Neighbor Device” when the failure
range is an adjacent router. Go to Subsection 7.5.1.6, “Inspection of
Unicast Routing Information” when it is a remote router.
7.5.1.4 Determination of Failure Range (Echo Test from Other End Device)
When or where login to the own router is not available, follow the procedure below to
determine the failure range of the communication from the other end device.
Step 1. Ensure that the other end device supports the ping command.
Step 2. Use the ping command to check accessibility between the other end device
and the destination.
Step 3. When communication to the destination turns out to be missing with the
ping command, use ping again to see if communication to the destination
from the device closest to the other end device is available.