eSpace IAD
Troubleshooting
2 Analy zing and Rectify ing Faults
Issue 02 (2012-02-29)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
40
2.3.3 Network Connection Failure
Symptom
The network between the IAD and other devices on the network is disconnected (network
status cant be tested by running the
ping
command).
Cause
The possible causes are as follows:
Issues of network cables, power supply, or network negotiation.
The IP address of the IAD conflicts with that of the other devices.
Packet loss.
When the Virtual LAN ( VLAN) is used, the IAD is not connected to the same VLAN as
the other devices.
The uplink port of the IAD which is used to connect the IAD to the superior devices and
the port which is used for cascading connections cannot be set as the destination
mirrored port.
Solution
1.
Check whether the network indicator is on. For details, see
2.
If the network cable connection is good, run the
display ipaddress
command to check
the IP address of the IAD. If the IP address of the IAD conflicts with that of other
devices (shares the same IP address with other devices), change the IP address of the
IAD.
3.
If an IP network exists between the IAD and the network destination device, you can run
the
tracert
command to check the connectivity of the network and ensure that the route
between the packet and the IP network is reachable.
4.
If no response is received after the
ping
a.b.c.d
command is executed. The possible
causes are as follows:
−
Some of the hosts or routers in the network closes the ping function.
−
The firewall used in the network can discard some of the packets according to the
defined conditions.
−
If a network is undertaken massive traffic , the Quality of Service (QoS) mechanism
may cause packet loss also.
−
If a packet is too big, the CPU usage of the IAD raises. Therefore, the IAD discards
all packets that need to be divided into fragments.
Fragment: The Internet protocol allows packets to be divided into fragments so that the fragments can go
through a link in the form of M aximum Transmission Unit (MTU).
5.
If VLAN is set on the IAD or the network destination device and the two devices are not
in the same VLAN, packets cannot be sent between the two devices.
6.
Run the
display monitor-port
command to check whether the uplink port or the port
used for cascading connections be set as the destination mirrored port. If yes, run the
undo monitor
command to cancel the configuration.