Routing to internet addresses ending with 255
I had this weird problem today, and I would like to know what caused it: I have two home servers, on different locations, on two ADSL lines using dynamic DNS. One is running Debian, the other FreeBSD 7.0-RELEASE. I usually ssh from one to the other. Today, the debian server had a public (internet) IP ending in 255. The FreeBSD 7.0 system refused to communicate with it. Another 6.3 system had no problem. The 6.3 and 7.0 system have identical adsl routers. Trying a traceroute from 7.0, it would seem the debian system was one hop away, which is of course incorrect. I understand that x.x.x.255 is ethernet's broadcast address. However 6.3 had no problem connecting to it, while 7.0 would not. Has something changed in FreeBSD, is this the intended behaviour or a bug? Furthermore, is it valid for my ISP to assign me an address ending in 255? The workaround was of course to ssh from another system, telnet into the router and reboot it so it gets another address. I would still like to know if there is any other solution. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
On Friday 16 May 2008 12:32:35 Manolis Kiagias wrote: I had this weird problem today, and I would like to know what caused it: I have two home servers, on different locations, on two ADSL lines using dynamic DNS. One is running Debian, the other FreeBSD 7.0-RELEASE. I usually ssh from one to the other. Today, the debian server had a public (internet) IP ending in 255. The FreeBSD 7.0 system refused to communicate with it. Another 6.3 system had no problem. The 6.3 and 7.0 system have identical adsl routers. Trying a traceroute from 7.0, it would seem the debian system was one hop away, which is of course incorrect. I understand that x.x.x.255 is ethernet's broadcast address. No, it's not. Since these days IP is classless, a network (and thus its broadcast address) is completely local information, not known to remote hosts. What might look to an external observer as a /24 network, may be something else. For example 213.0.0.255/24 may be the broadcast address for net 213.0.0.0/24, but it's not the broadcast address for net 213.0.0.0/23, which would be 213.0.1.255. Also, regadless of being the broadcast address or not, to the external observer that address is just an IP address. The router of the network will handle specially(will broadcast) the packet if it's destined for the broadcast address. However 6.3 had no problem connecting to it, while 7.0 would not. Has something changed in FreeBSD, is this the intended behaviour or a bug? This looks like a bug. Can you post more info about it? Furthermore, is it valid for my ISP to assign me an address ending in 255? Yes, assuming that you speak of a PPP connection. There is no network concept in PPP. The two peer addresses are totally unrelated. For example, a PPP interface configured with 10.0.0.1 -- 172.16.255.255 is perfectly valid configuration. HTH, Nikos ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
I have two home servers, on different locations, on two ADSL lines using dynamic DNS. One is running Debian, the other FreeBSD 7.0-RELEASE. I usually ssh from one to the other. Today, the debian server had a public (internet) IP ending in 255. The FreeBSD 7.0 system refused to communicate with it. Another 6.3 system had no problem. The 6.3 and 7.0 doesn't your 7.0 system has same first 3 bytes of IP, and badly set netmask to /24 instead of narrower? i don't think it's freebsd version dependent, unless developers made a bug. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
Wojciech Puchar wrote: I have two home servers, on different locations, on two ADSL lines using dynamic DNS. One is running Debian, the other FreeBSD 7.0-RELEASE. I usually ssh from one to the other. Today, the debian server had a public (internet) IP ending in 255. The FreeBSD 7.0 system refused to communicate with it. Another 6.3 system had no problem. The 6.3 and 7.0 doesn't your 7.0 system has same first 3 bytes of IP, and badly set netmask to /24 instead of narrower? i don't think it's freebsd version dependent, unless developers made a bug. all these systems are behind ADSL routers and use NAT. Their internal addresses are in the 192.168.0.X range. I could easily consider this a problem of the (cheap) ADSL routers, but 6 and 7 use the same model (OTOH, there may be different firmware versions). ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
Nikos Vassiliadis wrote: On Friday 16 May 2008 12:32:35 Manolis Kiagias wrote: I had this weird problem today, and I would like to know what caused it: I have two home servers, on different locations, on two ADSL lines using dynamic DNS. One is running Debian, the other FreeBSD 7.0-RELEASE. I usually ssh from one to the other. Today, the debian server had a public (internet) IP ending in 255. The FreeBSD 7.0 system refused to communicate with it. Another 6.3 system had no problem. The 6.3 and 7.0 system have identical adsl routers. Trying a traceroute from 7.0, it would seem the debian system was one hop away, which is of course incorrect. I understand that x.x.x.255 is ethernet's broadcast address. No, it's not. Since these days IP is classless, a network (and thus its broadcast address) is completely local information, not known to remote hosts. What might look to an external observer as a /24 network, may be something else. For example 213.0.0.255/24 may be the broadcast address for net 213.0.0.0/24, but it's not the broadcast address for net 213.0.0.0/23, which would be 213.0.1.255. Also, regadless of being the broadcast address or not, to the external observer that address is just an IP address. The router of the network will handle specially(will broadcast) the packet if it's destined for the broadcast address. I guessed it would be like this. Thank you for clarifying it. However 6.3 had no problem connecting to it, while 7.0 would not. Has something changed in FreeBSD, is this the intended behaviour or a bug? This looks like a bug. Can you post more info about it? Problem is I've already reset the router that had the .255 address. All other actions had no effect: - Restarting the network interface in 7.0 - Restarting routing / erasing and reconfiguring routing table in 7.0 - Trying the IP address directly instead of the dyndns.org name (clearly not any type of DNS problem) - Restarting the router connected to 7.0 Traceroute gave a result like: traceroute xxx.dyndns.org traceroute to xxx.dyndns.org (xxx.xxx.xxx.255), 64 hops max, 40 byte packets 1 xxx.dyndns.org (xxx.xxx.xxx.255) 1.008 ms 1.084 ms 0.928 ms Clearly wrong, since everything goes through my router: traceroute www.otenet.gr traceroute to www.otenet.gr (62.103.128.215), 64 hops max, 40 byte packets 1 router (192.168.0.55) 1.014 ms 0.948 ms 0.941 ms 2 athe10kt-l1.otenet.net (62.103.129.42) 19.399 ms 20.362 ms 19.892 ms ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
i don't think it's freebsd version dependent, unless developers made a bug. all these systems are behind ADSL routers and use NAT. Their internal addresses are in the 192.168.0.X range. I could easily consider this a problem of the (cheap) ADSL routers, but 6 very likely. yesterday i configured chinese 5 WLAN/LAN switch/routers, it looks like it's software was written by someone during single lunch break ;) i found 2 bugs not even searching much. but - as just a LAN/WLAN bridges they work fine. and 7 use the same model (OTOH, there may be different firmware versions). but WHAT are external IP's of these routers. this is important. if the problem host is A.B.C.255 check if routers external IP isn't A.B.C.something ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
Wojciech Puchar wrote: i don't think it's freebsd version dependent, unless developers made a bug. all these systems are behind ADSL routers and use NAT. Their internal addresses are in the 192.168.0.X range. I could easily consider this a problem of the (cheap) ADSL routers, but 6 very likely. yesterday i configured chinese 5 WLAN/LAN switch/routers, it looks like it's software was written by someone during single lunch break ;) i found 2 bugs not even searching much. but - as just a LAN/WLAN bridges they work fine. I too, am very well aware of the quality of these systems :) and 7 use the same model (OTOH, there may be different firmware versions). but WHAT are external IP's of these routers. this is important. if the problem host is A.B.C.255 check if routers external IP isn't A.B.C.something No, I just checked again with DynDNS update logs and all three routers had very different IP addresses at the time I was trying. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: [SOLVED] Routing to internet addresses ending with 255
Manolis Kiagias wrote: Wojciech Puchar wrote: i don't think it's freebsd version dependent, unless developers made a bug. all these systems are behind ADSL routers and use NAT. Their internal addresses are in the 192.168.0.X range. I could easily consider this a problem of the (cheap) ADSL routers, but 6 very likely. yesterday i configured chinese 5 WLAN/LAN switch/routers, it looks like it's software was written by someone during single lunch break ;) i found 2 bugs not even searching much. but - as just a LAN/WLAN bridges they work fine. I too, am very well aware of the quality of these systems :) and 7 use the same model (OTOH, there may be different firmware versions). but WHAT are external IP's of these routers. this is important. if the problem host is A.B.C.255 check if routers external IP isn't A.B.C.something No, I just checked again with DynDNS update logs and all three routers had very different IP addresses at the time I was trying. Checking with the internal log of the router confirmed the suspicions of people answering my question: The adsl router is responsible for the problem with the 255 address. It seems it cuts out these addresses as some kind of attack. No changes in configuration (firewall, protection and so on) on the router itself disables it. It seems I will have to live with it ;) Oh well... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Routing to internet addresses ending with 255
but WHAT are external IP's of these routers. this is important. if the problem host is A.B.C.255 check if routers external IP isn't A.B.C.something No, I just checked again with DynDNS update logs and all three routers had very different IP addresses at the time I was trying. try freebsd 6 (from livecd etc.) in place of freebsd 7 on the same computer. you will check if it's FreeBSD 7 problem (i DO NOT think so) or this crappy router. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: [SOLVED] Routing to internet addresses ending with 255
Checking with the internal log of the router confirmed the suspicions of people answering my question: The adsl router is responsible for the problem with the 255 address. It seems it cuts out these addresses as some kind of attack. No changes in configuration (firewall, protection and so on) on the router itself disables it. It seems I will have to live with it ;) Oh well... software designed heard somewhere that .0 and .255 addresses are not end nodes, and software simply drops all packet like that. please tell what router is it, to warn others. my bet is TP-LINK. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: [SOLVED] Routing to internet addresses ending with 255
Wojciech Puchar wrote: Checking with the internal log of the router confirmed the suspicions of people answering my question: The adsl router is responsible for the problem with the 255 address. It seems it cuts out these addresses as some kind of attack. No changes in configuration (firewall, protection and so on) on the router itself disables it. It seems I will have to live with it ;) Oh well... software designed heard somewhere that .0 and .255 addresses are not end nodes, and software simply drops all packet like that. please tell what router is it, to warn others. my bet is TP-LINK. Actually, it is a Sagem... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
