Hitachi GR2000 Series - Manual (Page 215)

Troubleshooting
GR2K-GA-0015 7-49
Ver. 07-02
Procedure for changing the MSS information
Confirm the setting value of mss for the PPPoE information by using the
configuration definition command (CLI type 1)
show pppoe .
[Result of the execution]
7.5.4 Troubleshooting NAT Communication Failures
Three factors that may produce communication troubles in the NAT and NAPT are as
follows:
1. Error in setting the configuration defining information related to NAT and NAPT.
2. Changes in the network configuration.
3. Impediments in the relaying network.
Regarding 2 above, investigate the difference in the network configuration before and
after the change, and check for any cause that may hinder communication.
This section assumes that the setting of a network card and cable connections has
been confirmed and explains the impediment positions and the procedure for
dividing the causes thereof in cases as shown in 1 and 3 above that: “no IP
communication is possible even though the configuration defining information and
the network configuration are correct,” “IP communication is no longer possible
because the configuration defining information was changed” or “conversion of the IP
address and the port number has become impossible.”
See Table 7-15, DHCP Client Communication Failures Troubleshooting Chart, for a
flowchart for troubleshooting these failures.
(config)# show pppoe OsakaISP1
pppoe Department2 OsakaISPÇP {
user_name "user2@osakaisp2";
password "osakaisp2password";
authentication_protcol chap;
echo_interval 3600;
mru 1492;
mss 1414;
};
(config)# pppoe OsakaISP1 -mss 1408
(config)# pppoe OsakaISP1 -mss 1
(config)# quit
# close OsakaISP1
# free OsakaISP1
#
Set a value smaller than the current
setting, or perform auto setting (1).
Input the next command to make the setting
information effective.
current mss value.