The proxy server is refusing to accept the connection. How to fix?

Question

Squid

On all computers on the local network, the connection to the Internet began to disappear, the browser writes "The proxy server refuses to accept the connection." The server based on Centos 6.4 worked in normal mode for about 3 years, and in the last 4 days the Internet appears on the network computers, then disappears by itself. And in the first half of the day everything works stably, then problems begin.
You can update the link address in the browser several times in a row and the Internet will work for a short time on some next update.
SQUID proxy installed, there are 3 subnets.
I haven't changed anything on the server lately, just one fine day it started working like that.
Could this be a problem with the server's network card, which goes into the local network?
On the server itself, the Internet works great!
Log SQUID SQUID
itself
Can it be affected by the same address in the network? Static distribution of addresses is configured.

Answer 1

well, what do you want someone to work for you, hire an admin, and you yourself can read the logs using the same google translate