I'm having problems connecting my LAN to aDSL.
I run a Mac Mini server with a fixed IP address, and my own named, smtpd, httpd, etc. There are two other Ethernet computers, and an Airport Extreme WiFi router (configured as a bridge), running through an 8-port switch and a D-Link router/firewall. The DLink router translates my fixed IP directly to the Mac Mini, and the others are getting DHCP from my router.
The most noticeable symptom is web pages loading slowly or incompletely, mail not getting through, and DOWN reports from external monitoring services.
If I ping my ISP's edge router (directly from my router, or from any connected computer), it is extremely intermittent. It can be 100% for tens of seconds straight, then 50% or more packet loss for tens of seconds straight.
ping -A -n -c 10 126.96.36.199 PING 188.8.131.52 (184.108.40.206): 56 data bytes 64 bytes from 220.127.116.11: icmp_seq=0 ttl=254 time=22.780 ms 64 bytes from 18.104.22.168: icmp_seq=1 ttl=254 time=23.520 ms Request timeout for icmp_seq 2 Request timeout for icmp_seq 3 Request timeout for icmp_seq 4 64 bytes from 22.214.171.124: icmp_seq=5 ttl=254 time=23.207 ms 64 bytes from 126.96.36.199: icmp_seq=6 ttl=254 time=23.774 ms Request timeout for icmp_seq 7 64 bytes from 188.8.131.52: icmp_seq=8 ttl=254 time=23.608 ms 64 bytes from 184.108.40.206: icmp_seq=9 ttl=254 time=24.670 ms --- 220.127.116.11 ping statistics --- 10 packets transmitted, 6 packets received, 40.0% packet loss round-trip min/avg/max/stddev = 22.780/23.593/24.670/0.579 ms
If I hook a computer directly to the aDSL modem via DHCP, everything works, so my ISP says, "Sorry, that's YOUR problem, NOT ours." They've had a phone company tech out to the network interface, who says everything is fine there.
But if I plug even a second computer in (both computers relatively quiescent), via router or switch, then packets begin to get dropped.
I understand that if all my computers were doing huge downloads at the same time, I could expect packet loss. But this happens simply by plugging in a second computer that is doing no network traffic.
Here's the weird part: after having my laptop plugged directly into the aDSL modem and seeing 100% success, if I plug it into my "normal" network, things will work just fine for several minutes before packets start getting dropped again! I can run 100% ping tests on any computer on my LAN, and things work fine for several minutes.
To me, this smells of "traffic shaping," where the ISP is detecting that I have more than one computer plugged in, and then reduces bandwidth. They claim they don't do that.
I'm pretty knowledgable about networking, but this has me stumped.
I'm at my wits end. Any ideas how to debug and fix this?
UPDATE +1 to "sawdust" for suggesting I go back to basics. I paired the laptop with different combinations of other computers, and found that only when the Mac Mini Server AND the D-Link were hooked up, things went south. I took the router out, and hooked the switch directly to the modem, and things started working. Thanks, D-Link.
This is a configuration I thought I had tried before, but I guess not, or something else was wrong at the time.
But now I can't get my printer working. It keeps wanting to be in the 10.129 network, and other computers can't see it there. Keep working on it, I guess...