An office is connected to the private network through the USG2210. The connection between the intranet and the private network is intermittent.
1. Check whether the parameters of the USG2210 and those of the interoperating device are consistent. The rate and duplex are consistent. Therefore, this possibility is ruled out.
2. Capture packets on the intranet PC and run the AV software. Compare the captured packets with the ARP table on the USG2210. No gateway spoofing is discovered. The ARP spoofing is ruled out. 3. According to the diagnosis of the log information, IP address conflict is discovered. The IP address of a virtual machine on the intranet is the same as that of the intranet interface of the USG2210. Turn off the virtual machine. The communication restores to normal.
1. The interface parameters of the interoperating device are inconsistent.
2. ARP attacks exist on the intranet.
3. The IP addresses conflict.
Normally, the intermittent network access is caused by inconsistent parameters, IP conflict, IP attack, or the quality of the network link. Locate the fault one by one.