Why is access to 2nd LAN (via squid) failing?

Question

I'm having a problem with a very simple squid configuration.

My network is configured as shown:

=== 192.168.3.xxx LAN === (eth1 - .100)[proxy host](.18.240.66 - eth0) === 10.x.x.x LAN

I want to proxy requests from the 192.168.3.0/24 LAN to the 10.0.0.0/8 LAN. I've set up the proxy settings on 192.168.3.200 to use the proxy at 192.168.3.100:8080. The proxy request arrives at the proxy just fine, but it doesn't seem to go out on eth0. I've verified both of these with Wireshark.

In particular, I'm trying to send a HTTP request from 192.168.3.200 to 10.63.78.243 via the proxy. This is what ends up in the squid access.log:

192.168.3.200 TCP_MISS/000 0 GET http://10.63.78.243:8080/path/server.jsp? - DIRECT/10.63.78.243 -

The packet sent from .200 to .100:8080 has this content (via Wireshark):

GET http://10.63.78.243:8080/path/server.jsp?x=x HTTP/1.1
Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms-xpsdocument, application/xaml+xml, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*
Accept-Language: en-us
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; InfoPath.1; MS-RTC LM 8)
Accept-Encoding: gzip, deflate
Proxy-Connection: Keep-Alive
Host: 10.63.78.243:8080

I have the following squid configuration:

#
# Recommended minimum configuration:
#
acl manager proto cache_object
acl localhost src 127.0.0.1/32 ::1
acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1

# Example rule allowing access from your local networks.
# Adapt to list your (internal) IP networks from where browsing
# should be allowed
acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
acl localnet src 172.16.0.0/12  # RFC1918 possible internal network
acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
acl localnet src fc00::/7       # RFC 4193 local private network range
acl localnet src fe80::/10      # RFC 4291 link-local (directly plugged) machines
acl RDnet dst 10.0.0.0/8

acl SSL_ports port 443
acl Safe_ports port 80      # http
acl Safe_ports port 21      # ftp
acl Safe_ports port 443     # https
acl Safe_ports port 70      # gopher
acl Safe_ports port 210     # wais
acl Safe_ports port 1025-65535  # unregistered ports
acl Safe_ports port 280     # http-mgmt
acl Safe_ports port 488     # gss-http
acl Safe_ports port 591     # filemaker
acl Safe_ports port 777     # multiling http
acl CONNECT method CONNECT

#
# Recommended minimum Access Permission configuration:
#
# Only allow cachemgr access from localhost
http_access allow manager localhost
http_access deny manager

# Deny requests to certain unsafe ports
http_access deny !Safe_ports

# Deny CONNECT to other than secure SSL ports
http_access deny CONNECT !SSL_ports

# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on "localhost" is a local user
#http_access deny to_localhost

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#

# Example rule allowing access from your local networks.
# Adapt localnet in the ACL section to list your (internal) IP networks
# from where browsing should be allowed
http_access allow localnet
http_access allow localhost
http_access allow RDnet

# And finally deny all other access to this proxy
http_access deny all

# Squid normally listens to port 3128
http_port 8080

# We recommend you to use at least the following line.
hierarchy_stoplist cgi-bin ?

# Uncomment and adjust the following to add a disk cache directory.
#cache_dir ufs /var/spool/squid 100 16 256

# Leave coredumps in the first cache dir
coredump_dir /var/spool/squid

# Add any of your own refresh_pattern entries above these.
refresh_pattern ^ftp:       1440    20% 10080
refresh_pattern ^gopher:    1440    0%  1440
refresh_pattern -i (/cgi-bin/|\?) 0 0%  0
refresh_pattern .       0   20% 4320

netstat -rn gives the following:

[root@localhost squid]# netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
192.168.3.0     0.0.0.0         255.255.255.0   U         0 0          0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0 virbr0
10.18.240.0     0.0.0.0         255.255.248.0   U         0 0          0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth1
0.0.0.0         10.18.247.254   0.0.0.0         UG        0 0          0 eth0

I read that as routing any packet (including those to 10.63.78.243) to 10.18.247.254 via eth0. I know it's reachable (see this output of ping -R)

[root@localhost squid]# ping -c 1 -R 10.63.78.243
PING 10.63.78.243 (10.63.78.243) 56(124) bytes of data.
64 bytes from 10.63.78.243: icmp_seq=1 ttl=50 time=377 ms
RR:     10.18.240.66
    10.138.156.186
    10.17.182.22
    10.190.11.66
    112.78.255.4
    198.19.1.41
    10.143.222.81
    10.143.222.98
    172.31.206.129


--- 10.63.78.243 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 377ms
rtt min/avg/max/mdev = 377.644/377.644/377.644/0.000 ms

Any thoughts? One thought I'm having is that Squid receives the request just fine and tries to send it but.... Where might it be going? This host only has the 2 interfaces, and packets to 10.x.x.x should be going out eth0. But no packet shows up in Wireshark. So I'm a little lost.

UPDATE: Added the following to the configuration file:

cache_peer 10.159.3.23 parent 8080 0 default

That allowed my proxy to forward requests to the proxy that actually can reach the 10.63.78.243 host.

Answer 1

MISS/000 means aborted, not sure it's from client or no answer back after passing the request to 10.63.78.243:8080

What do you get with a "telnet 10.63.78.243 8080" FROM the squid host ? GET / HTTP/1.1 Host: 10.63.78.243:8080