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OK, this one's a little confusing. Background: janus.thekramers.net is my server and my firewall, running Fedora 8. eth0 (static IP address 75.149.142.17) goes to my cablemodem and eth1 goes to my intranet via a switch. For a long time (I don't know when it started), images from many websites would not load, and trying to wget the URL of the image would hang, when browsing (using any browser) on janus. The images load fine on machines in my intranet, so they're coming in through the cablemodem and out through eth1, but cannot be accessed locally. I came to the realization yesterday that if you follow the rabbit hole down, the images from all these websites were served by IP addresses owned by Akamai. AHA! There are hundreds of lines like this in /var/log/messages with 96.17.x.x: # grep 96.17 /var/log/messages Dec 25 11:10:08 janus kernel: Inbound IN=eth0 OUT= MAC=00:50:8d:b3:d5:2a:00:13:f7:be:31:76:08:00 SRC=96.17.73.19 DST=75.149.142.17 LEN=44 TOS=0x00 PREC=0x20 TTL=59 ID=0 DF PROTO=TCP SPT=80 DPT=51598 WINDOW=5840 RES=0x00 ACK SYN URGP=0 Dec 25 11:11:42 janus kernel: Inbound IN=eth0 OUT= MAC=00:50:8d:b3:d5:2a:00:13:f7:be:31:76:08:00 SRC=96.17.72.33 DST=75.149.142.17 LEN=44 TOS=0x00 PREC=0x20 TTL=59 ID=0 DF PROTO=TCP SPT=80 DPT=57413 WINDOW=5840 RES=0x00 ACK SYN URGP=0 Dec 25 11:11:42 janus kernel: Inbound IN=eth0 OUT= MAC=00:50:8d:b3:d5:2a:00:13:f7:be:31:76:08:00 SRC=96.17.73.19 DST=75.149.142.17 LEN=44 TOS=0x00 PREC=0x20 TTL=59 ID=0 DF PROTO=TCP SPT=80 DPT=51598 WINDOW=5840 RES=0x00 ACK SYN URGP=0 I found this in iptables NR chain: LSI all -- 96.0.0.0/8 75.149.142.16/30 The other reference to the NR chain is NR all -- !75.149.142.16/30 0.0.0.0/0 You can see my whole iptables dump at http://thekramers.net/tmp/iptables_dump In fact, there are quite a few lines in that chain with x.0.0.0/8. I don't know a ton about iptables, so I'm sorry if some of these questions are a little basic. 1) Does that rule look like it blocks all of 96.? 2) How would that have gotten in there? I can't imagine I put it in there myself? 3) How could the rule block the IP address on Janus but let it through to my intranet? 4) How can I drop that rule to test it out? Should I? 5) How can I delete that rule permanently? I see there's a /etc/sysconfig/iptables and /etc/sysconfig/iptables-config, but neither file seems to hold all those rules. 6) This is a side question, but how can I get firewall messages to go to some other file than /var/log/messages? I get so many it's impossible to find other messages. Thanks, and have a great holiday!
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