Hitachi GR2000 Series - Manual (Page 211)

Troubleshooting
GR2K-GA-0015 7-45
Ver. 07-02
Regarding 1 and 2 above, investigate the difference in the configuration defining
information and the network configuration before and after the change. Finally,
check for any cause that might hinder communication.
This chapter assumes that client setting (setting of a network card and connection of
cables) has been confirmed, and explains the impediment positions “caused by the
mru and mss settings” in the event that “communication is impossible (a particular
HP cannot be accessed),” and explains the procedure for dividing the cause thereof
by using the settings described in 3 and 4 above.
For the impediment positions and the procedure for dividing the causes thereof,
follow the flow given below.
Figure 7-15 PPPoE Communication Failures Troubleshooting Chart
7.5.3.1 Inspection of Log Message and Interface
Impediment (or breakage) of the hardware (RP/NIF/Line) or impediment in the
adjacent device may be seen as the cause of the communication obstruction. Inspect
the log messages shown in the router and the interface up/down status by the
show
ip interface command. For the procedure, see Subsection 7.5.1.
Note: Disconnection of PPPoE session during occurrence of RP congestion
<Cannot communicate>
Check for any presence of physical failure
with the show logging command.
Inspect interface up/down status
with show ip interface command.
Follow the procedure for each log
message according to the Operation log
and MIB, and follow the procedure for
troubleshooting on IP communication
failures according to 7.5.1.
Physical error log
not found
Physical error log
found
Determine failure range
with the ping command.
Follow the procedure in Section 7.4,
“Communication failure in network
interface”.
Unable to
communicate with
neighbor host/router
Inspect route information with the
show ip route command.
Go to Section 7.4,
“Communication failure in
network interface”.
Perform troubleshooting based
on routing protocol
Not connected
Change of mru (MTU) information
Route information
available
Unable to communicate with the neighbor and remote hosts/routers.
Unable to communicate with remote host/router
Inspect route the connected
status with the show interfaces
command
Invalid next hop address
Route information not
available
Change of MSS
information
up
down
connected