How to Troubleshoot the Network Configuration Fault in IP SAN Applications of the S5100 Storage Device?

1. Version: The storage device is Huawei S5100. The server is Dell860. The operating system is SUSE 9 SP3. The switch is Huawei Quidway3026. 2. Network overview: For the network, refer to the figure in the attachment. 3. Fault symptom: After the server is restarted, the running speed of the LUNs is slow. The fdisk-l command is executed two minutes later. Only part of LUNs have been mounted to the server, other LUNs are being mounted (usually, it takes a few seconds to mount all LUNs). After all LUNs are discovered, the mount command is executed to check the mounted file systems. No file system is successfully mounted (File systems can be automatically mounted after startup).

None

Step 1  Check the IP addresses of the network adapter in the server and the service port on the S5100.
Step 2  Check the configuration of the Quidway3026 switch. The rate and working mode of the switch port connected to the server are set to 100 Mbit/s and full-duplex. Usually, the server network adapter is auto-adaptive; therefore, the working mode of the switch port connected to the server should be set to auto.
Step 3  Run the following commands on the switch:
int e0/20
undo speed
undo  duplex
Save the operations and exit.
Step 4  Ping the IP address of the service port on the S5100 from the server. The response time of most data packets is shorter than 1 ms.
Step 5  Restart the server. All LUNs are discovered in a short time and file systems can be automatically mounted.

1. The storage device has been connected to the target by using the iSCSI protocol.
2. It takes about four minutes to mount all LUNs by running the fdisk-l command.
3.The mount command is executed to check the mounted file systems. No file system is successfully mounted (The system is set to automatically mount file systems after startup).
4. The ping command is executed to check the connection between the server and the service port on the S5100. The response time changes a lot. Most of response time is 123 ms. According to the phenomena above, a network fault is initially located.

Do not change the configuration of the switch port connected to the server. The rate and working mode of the port are set to auto-adaptive by default.