The software version of our switch is v2.03, model is SS3 4228G and also 4250T.
We've set a management ip in the 4228G/4250T switch and we used all the factory default settings. Then we connected an IBM notebook to the switch FastEthernet port using a straight cable. We started the ping on the DOS prompt using 1500 bytes and saw a serious packet loss. We used the sniffer program on the notebook to capture the packets in and out of the NIC of notebook and we found that when we saw a "Request time out" in the DOS prompt, the sniffer actually captured an "Echo reply" from the switch. However, this "Echo reply" is so weird that it has the following strange things:
1) The destination MAC address (which should be the MAC of the notebook) became "BABABABABABA" (I'm not joking).
2) There is an ICMP header checksum error.
We try the following modification to the switch settings but still have the above symptoms:
1) Set the switch port to 100full and the NIC of notebook to 100full
2) Use normal STP instead of Rapid STP
3) Disable STP globally
4) Disable flow control on that port
4) Disable Broadcast Storm control
However when we connected another notebook to the switch and ping from notebook to notebook using 1500 bytes, there was no problem. And when we use 1460 bytes to ping from notebook to switch, there was no problem too.
Even more weird things started when we started to use 1461 bytes to 1480 bytes to ping from notebook to switch. The following addition symptoms occurred:
1) Some weird unknown ethernet packets with both source and destination MAC address as "BABABABABABA" and the content of the packet is actually "abcdefg...xyz" which is the ICMP data content when we ping using DOS prompt.
2) When we used 1480 bytes to ping from notebook to switch, the sniffer capture showed that there are some "Echo" (not "Echo reply"
packets with source IP = switch IP, but destination IP = 186.186.186.186, and an ICMP checksum error. I've checked that 186 is actually "BA" in hex form....
Any help would be very appreciated. Thanks.
We've set a management ip in the 4228G/4250T switch and we used all the factory default settings. Then we connected an IBM notebook to the switch FastEthernet port using a straight cable. We started the ping on the DOS prompt using 1500 bytes and saw a serious packet loss. We used the sniffer program on the notebook to capture the packets in and out of the NIC of notebook and we found that when we saw a "Request time out" in the DOS prompt, the sniffer actually captured an "Echo reply" from the switch. However, this "Echo reply" is so weird that it has the following strange things:
1) The destination MAC address (which should be the MAC of the notebook) became "BABABABABABA" (I'm not joking).
2) There is an ICMP header checksum error.
We try the following modification to the switch settings but still have the above symptoms:
1) Set the switch port to 100full and the NIC of notebook to 100full
2) Use normal STP instead of Rapid STP
3) Disable STP globally
4) Disable flow control on that port
4) Disable Broadcast Storm control
However when we connected another notebook to the switch and ping from notebook to notebook using 1500 bytes, there was no problem. And when we use 1460 bytes to ping from notebook to switch, there was no problem too.
Even more weird things started when we started to use 1461 bytes to 1480 bytes to ping from notebook to switch. The following addition symptoms occurred:
1) Some weird unknown ethernet packets with both source and destination MAC address as "BABABABABABA" and the content of the packet is actually "abcdefg...xyz" which is the ICMP data content when we ping using DOS prompt.
2) When we used 1480 bytes to ping from notebook to switch, the sniffer capture showed that there are some "Echo" (not "Echo reply"
packets with source IP = switch IP, but destination IP = 186.186.186.186, and an ICMP checksum error. I've checked that 186 is actually "BA" in hex form....Any help would be very appreciated. Thanks.