Re: neighbours not returning images?

- I am seeing a strage effect where if a request is made to the proxy for
- an image file that a neighbour has, the proxy returns an error 61
- (Connection refused) despite the fact that the neighbour appears to
- believe it has delivered the item and direct access (without proxy) is
- successful.
-
- Log details below. Does anyone have any ideas as to what may be going
- wrong ?
-
- On PROXY1 the access log returns:
- access.log:130.102.128.96 - - [30/Sep/1996:14:38:38 +1000] "GET
- http://www.unitedmedia.com/comics/dilbert/archive/dilbert960911-4053.gif"
- ERR_CONNECT_FAIL 945
-
- But the hierarchy log seems to indicate that the neighbour did offer the
- object:
- hierarchy.log:[30/Sep/1996:14:38:38 +1000]
- http://www.unitedmedia.com/comics/dilbert/archive/dilbert960911-4053.gif
- NEIGHBOR_HIT lyrebird.cc.uq.oz.au
-
- store.log:844058318.365 RELEASE 400 300 [ 5m] 0/945
- 1285/GET/http://www.unitedmedia.com/comics/dilbert/archive/dilbert960911-4053.gif
-
- PROXY2 appears to log a sucessful hit:
- access.log:130.102.2.60 - - [30/Sep/1996:14:38:38 +1000] "ICP_QUERY
- http://www.unitedmedia.com/comics/dilbert/archive/dilbert960911-4053.gif"
- UDP_HIT 93
-

        I ran into something similar on one occasion, I suggest you check the
'cache_host' line for the tcp (http) port & icp port numbers. If you have the
tcp port number wrong but the icp port correct you will send icp queries
correctly and received UDP_HIT_OBJ's that fool you into thinking the
configuration is correct but large objects will fail since you don't have the
correct tcp port in your config file. From memory 'ERR_CONNECT_FAIL ...' is
the
error you get in this case.

        A lot of proxy servers DONT use the 3128 address for proxy server tcp
(http) port. It would be a good idea if multiple http ports could specified
so that exisiting port could continue to be supported and still have 3128
active as well.

        The http://www.nlanr.net/Cache/Tracker/ registration database is useful
in these cases for checking your config against your neighbour/parent(s).
The registration database needs to be promoted more as a solution to this
problem if nothing else.

-- 
Neil Murray                              Email:  neil@aone.com.au
Access One Pty. Ltd.                     http://www.aone.net.au/
41 Malcolm Rd., Braeside                 Phone:  +61 3 9239 1444
Victoria, Australia  3195                Fax:    +61 3 9580 5581