php editor Xinyi teaches you how to solve the problem of gateway Ping failure. Failure to ping the gateway may be caused by network connection problems, firewall blocking, IP address setting errors, etc. When troubleshooting problems, you can check whether the network connection is normal, check the firewall settings, confirm whether the IP address is correct, etc. By gradually checking and eliminating possible causes, you can solve the problem of gateway ping failure and ensure smooth network connection.
Reasons why pinging on the same network segment fails
There are usually two situations when the ping command cannot connect: one is an IP address that cannot be pinged in the same network segment, and the other is an IP address that cannot be pinged in a different network segment. These two situations have different solutions. First, let’s discuss the situation where ping fails within the same network segment.
1. Ping fails on the same network segment, and the result is "unable to access the target host"
The destination IP and the source IP are in the same network segment. The result of ping is "unable to access the target host", and the ping request was not sent.
Let’s take a look at pinging an IP address that does not exist on the same network segment.
After the ping request is sent, the return message "Unable to access the target host" is displayed.
What’s the reason?
It means that at this time, the ping request was not sent successfully. At this time, you need to check:
1. Is the other party turned on? Does the ip exist?
2. If there is a cross-switch VLAN, check whether the corresponding intermediate trunk link is connected?
3. Is the direct connection route correct? Should I take the default route instead of the direct route?
4. Whether the subnet mask is wrong.
5. Is the default gateway filled in correctly?
2. Ping fails on the same network segment, and the result is "time out"
The destination IP and source IP are in the same network segment. The result of ping is "timeout or time out". The ping request has been sent successfully, but the target host did not reply.
After the ping request is sent, "timeout" is displayed in the response.
What’s the reason?
In this case, the ping has been successfully sent and reached the host, but no response was received. Please check:
1. Check the firewall. The firewall prohibits responses to ping.
2. The subnet mask is set incorrectly, resulting in the devices not being on the same network segment.
3. The device hardware fails, resulting in the device not having a corresponding mac address, unable to generate a routing table, and taking the default route.
4. IP conflict, or the IP address and the direct route are not in the same network segment.
5. The gateway is not set up properly
Reason why ping fails across network segments
There are many possible reasons why ping fails on different network segments. Let’s take a look at the common reasons across network segments.
1. The ping fails across network segments, and the result is "Unable to access the target host"
If the target host cannot be accessed across network segments, it means that the request was not successfully sent and the destination IP address and mac address cannot be obtained.
Possible reasons are:
1. The destination IP address does not exist.
2. Check whether there is a default route in the routing table
3. Check whether the arp table contains the gateway’s mac address
4. There is a gateway setting error
5. Take the default route
2. Ping fails across network segments, and the result is "time out"
If time out is displayed, it means that the ping request message has been sent, and the gateway of the destination IP has obtained the mac address of the destination IP, but the destination host has not replied, or the source host cannot receive it. These should check the backhaul route and the node backhaul route.
Possible reasons are:
1. Check the firewall to see if it intercepts the ping request message.
2. Check whether the route through the node is correct or whether there is a return route.
3. The hardware network card outlet of the return route and the inlet network card of the ping request are not the same.
4. All the interfaces corresponding to the switch vlan are down, causing the vlan status to be down, and the corresponding route for the vlan is not generated.
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