TCP_HIT
Squid发现请求资源的貌似新鲜的拷贝，并将其立即发送到客户端。TCP_MISS
Squid没有请求资源的cache拷贝。TCP_REFERSH_HIT
Squid发现请求资源的貌似陈旧的拷贝，并发送确认请求到原始服务器。原始服务器返回304（未修改）响应，指示squid的拷贝仍旧是新鲜的。TCP_REF_FAIL_HIT
Squid发现请求资源的貌似陈旧的拷贝，并发送确认请求到原始服务器。然而，原始服务器响应失败，或者返回的响应Squid不能理解。在此情形下，squid发送现有cache拷贝（很可能是陈旧的）到客户端。TCP_REFRESH_MISS
Squid发现请求资源的貌似陈旧的拷贝，并发送确认请求到原始服务器。原始服务器响应新的内容，指示这个cache拷贝确实是陈旧的。TCP_CLIENT_REFRESH_MISS
Squid发现了请求资源的拷贝，但客户端的请求包含了Cache-Control: no-cache指令。Squid转发客户端的请求到原始服务器，强迫cache确认。TCP_IMS_HIT
客户端发送确认请求，Squid发现更近来的、貌似新鲜的请求资源的拷贝。Squid发送更新的内容到客户端，而不联系原始服务器。TCP_SWAPFAIL_MISS
Squid发现请求资源的有效拷贝，但从磁盘装载它失败。这时squid发送请求到原始服务器，就如同这是个cache丢失一样。TCP_NEGATIVE_HIT
在对原始服务器的请求导致HTTP错误时，Squid也会cache这个 响应。在短时间内对这些资源的重复请求，导致了否命中。negative_ttl指令控制这些错误被cache的时间数量。请注意这些错误只在内存 cache，不会写往磁盘。下列HTTP状态码可能导致否定cache（也遵循于其他约束）： 204, 305, 400, 403, 404, 405, 414, 500, 501, 502, 503, 504。TCP_MEM_HIT
Squid在内存cache里发现请求资源的有效拷贝，并将其立即发送到客户端。注意这点并非精确的呈现了所有从内存服务的响应。例如，某些cache在内存里，但要求确认的响应，会以TCP_REFRESH_HIT, TCP_REFRESH_MISS等形式记录。TCP_DENIED
因为http_access或http_reply_access规则，客户端的请求被拒绝了。注意被http_access拒绝的请求在第9域的值是NONE/-，然而被http_reply_access拒绝的请求，在相应地方有一个有效值。TCP_OFFLINE_HIT
当offline_mode激活时，Squid对任何cache响应返回cache命中，而不用考虑它的新鲜程度。TCP_REDIRECT
重定向程序告诉Squid产生一个HTTP重定向到新的URI（见11.1节）。正常的，Squid不会记录这些重定向。假如要这样做，必须在编译squid前，手工定义LOG_TCP_REDIRECTS预处理指令。NONE
无分类的结果用于特定错误，例如无效主机名。相应于ICP查询，下列标签可能出现在access.log文件的第四域。
UDP_HIT
Squid在cache里发现请求资源的貌似新鲜的拷贝。UDP_MISS
Squid没有在cache里发现请求资源的貌似新鲜的拷贝。假如同一目标通过HTTP请求，就可能是个cache丢失。请对比UDP_MISS_NOFETCH。UDP_MISS_NOFETCH
跟UDP_MISS类似，不同的是这里也指示了Squid不愿去处理相应的HTTP请求。假如使用了-Y命令行选项，Squid在启动并编译其内存索引时，会返回这个标签而不是UDP_MISS。UDP_DENIED
因为icp_access规则，ICP查询被拒绝。假如超过95%的到某客户端的ICP响应是UDP_DENIED，并且客户端数据库激活了（见附录A），Squid在1小时内，停止发送任何ICP响应到该客户端。若这点发生，你也可在cache.log里见到一个警告。UDP_INVALID
Squid接受到无效查询（例如截断的消息、无效协议版本、URI里的空格等）。Squid发送UDP_INVALID响应到客户端。TCP_HIT
A valid copy of the requested object was in the cache.
TCP_MISSThe requested object was not in the cache.
TCP_REFRESH_HITThe requested object was cached but STALE. The IMS query for the object resulted in “304 not modified”.
TCP_REF_FAIL_HITThe requested object was cached but STALE. The IMS query failed and the stale object was delivered.
TCP_REFRESH_MISSThe requested object was cached but STALE. The IMS query returned the new content.
TCP_CLIENT_REFRESH_MISSThe client issued a “no-cache” pragma, or some analogous cache control command along with the request. Thus, the cache
has to refetch the object.
TCP_IMS_HITThe client issued an IMS request for an object which was in the cache and fresh.
TCP_SWAPFAIL_MISSThe object was believed to be in the cache, but could not be accessed.
TCP_NEGATIVE_HITRequest for a negatively cached object, e.g. “404 not found”, for which the cache believes to know that it is
inaccessible. Also refer to the explainations for negative_ttl in your squid.conf file.
TCP_MEM_HITA valid copy of the requested object was in the cache and it was in memory, thus avoiding disk accesses.
TCP_DENIEDAccess was denied for this request.
TCP_OFFLINE_HITThe requested object was retrieved from the cache during offline mode. The offline mode never validates any object, see
offline_mode in squid.conf file.
UDP_HITA valid copy of the requested object was in the cache.
UDP_MISSThe requested object is not in this cache.
UDP_DENIEDAccess was denied for this request.
UDP_INVALIDAn invalid request was received.
UDP_MISS_NOFETCHDuring “-Y” startup, or during frequent failures, a cache in hit only mode will return either UDP_HIT or this code.
Neighbours will thus only fetch hits.
NONESeen with errors and cachemgr requests.
The following codes are no longer available in Squid-2:
ERR_*
Errors are now contained in the status code.
TCP_CLIENT_REFRESHSee: TCP_CLIENT_REFRESH_MISS.
TCP_SWAPFAILSee: TCP_SWAPFAIL_MISS.
TCP_IMS_MISSDeleted, TCP_IMS_HIT used instead.
UDP_HIT_OBJHit objects are no longer available.
UDP_RELOADINGSee: UDP_MISS_NOFETCH.