Squid_ The Definitive Guide - Duane Wessels [154]
The cache client list shows a handful of statistics for each client IP address accessing Squid, which looks like this:
Address: 206.168.0.9
Name: 206.168.0.9
Currently established connections: 0
ICP Requests 59000
UDP_HIT 1609 3%
UDP_MISS 57388 97%
UDP_INVALID 3 0%
HTTP Requests 11281
TCP_HIT 656 6%
TCP_MISS 3464 31%
TCP_REFRESH_HIT 4477 40%
TCP_REFRESH_MISS 767 7%
TCP_CLIENT_REFRESH_M 397 4%
TCP_IMS_HIT 1082 10%
TCP_SWAPFAIL_MISS 7 0%
TCP_NEGATIVE_HIT 13 0%
TCP_MEM_HIT 418 4%
The Address line, obviously, shows the client's IP address. Name is the same, unless you have log_fqdn enabled, and the DNS reports a name for the address. The Currently established connections line shows how many HTTP connections are currently open between the client and Squid.
If the client has sent any ICP queries, you'll see a breakdown of the results here. In this example, only 3% of this client's ICP queries were hits. Note, this page doesn't currently include HTCP result statistics. Finally, you'll see a breakdown of HTTP request result codes.
The client database consumes a fair amount of memory, especially if you have a large number of client IP addresses accessing Squid. You can disable the database entirely, thus conserving memory, with the client_db directive. Also note that there is no way to clear the counters or to remove entries while Squid is running.
netdb: Network Measurement Database
This page is available only with the ./configure —enable-icmp option (see Section 10.5). On this page you'll find quite a lot of IP addresses, hostnames, packet counters, and RTT values. It looks something like this:
Network DB Statistics:
Network recv/sent RTT Hops Hostnames
165.123.34.0 7/ 7 12.7 8.6 onlinebooks.library.upenn.edu
www.library.upenn.edu
digital.library.upenn.edu
rtp.us.ircache.net 17.0 11.0
sj.us.ircache.net 71.0 17.3
209.202.204.0 4/ 4 12.8 10.0 adbuyer3.lycos.com
rtp.us.ircache.net 20.6 15.0
sj.us.ircache.net 77.6 15.0
63.151.139.0 17/ 17 12.8 9.0 www.originlab.com
sj.us.ircache.net 80.0 12.0
209.68.20.0 23/ 23 12.8 11.7 www6.tomshardware.com www.guestbook.nu
rtp.us.ircache.net 34.9 15.1
sj.us.ircache.net 73.9 14.7
Each /24 network is listed, in order of increasing round-trip time. You can see how many ICMP pings have been sent and received, the average RTT, and the estimated router hop-count. The Hostnames field shows the hostnames that resolve to addresses within the /24 network. If Squid has ICMP measurements from its neighbors for the network, those are printed as well. In this example, the local cache is closer to all the networks than its neighbors (rtp.us.ircache.net and sj.us.ircache.net).
asndb: AS Number Database
Although this page is always available, it contains interesting data only if you are using one of the Autonomous System (AS) ACLs, such as src_as or dst_as.
When you use an AS-based ACL, Squid queries the Routing Arbiter database (whois.ra.net) to discover the IP networks associated with the AS number. The results of those queries are displayed on this page. The output looks like this:
Address AS Numbers
128.98.0.0/16 7
146.80.0.0/16 7
192.5.28.0/24 7
192.5.29.0/24 7
192.5.30.0/24 7
192.107.178.0/24 7
192.135.183.0/24 5637
194.61.177.0/24 7
194.61.180.0/24 7
194.61.183.0/24 7
194.83.162.0/24 7
carp: CARP Information
This page is available only with the ./configure —enable-carp option and if you have some CARP parents configured. Squid displays a table of all CARP parents, which looks like this:
Hostname Hash Multiplier Factor Actual
bo1.us.ircache.net f142425b 0.894427 0.400000 0.527950
bo2.us.ircache.net 12180f04 1.118034 0.600000 0.472050
Hash is the neighbor's hash value from the CARP algorithm. Multiplier is another value used by the algorithm. Factor is taken from the carp-load-factor option on the cache_dir line in squid.conf. Actual is the actual distribution of requests among the CARP parents. Ideally, it should match the Factor value.
server_list: Peer Cache Statistics
This page displays various counters and statistics for your