What is “Failure Ratio at 1.01; Going into hit-only-mode for 5 minutes\?
Consider a pair of caches named A and B. It may be the case that A can reach B, and vice-versa, but B has poor reachability to the rest of the Internet. In this case, we would like B to recognize that it has poor reachability and somehow convey this fact to its neighbor caches. Squid will track the ratio of failed-to-successful requests over short time periods. A failed request is one which is logged as ERR_DNS_FAIL, ERR_CONNECT_FAIL, or ERR_READ_ERROR. When the failed-to-successful ratio exceeds 1.0, then Squid will return ICP_MISS_NOFETCH instead of ICP_MISS to neighbors. Note, Squid will still return ICP_HIT for cache hits.
