Re: specifying scopid's for link-local IPv6 addrs
Rick Jones wrote: Rick, I don't see any way around this. For example, on one of my test systems, I have the following link local routes: chance% netstat -A inet6 -rn | grep fe80::/64 fe80::/64 :: U 25600 eth0 fe80::/64 :: U 25600 eth2 fe80::/64 :: U 25600 eth3 fe80::/64 :: U 25600 eth4 fe80::/64 :: U 25600 eth5 fe80::/64 :: U 25600 eth6 So if I want to run a link local test to fe80::202:b3ff:fed4:cd1, the system has no way to choose which is the correct interface to use for the test, and will give an error if the interface isn't specified. Yeah, I was wondering about that. I'm not sure if the attempts on those other OSes happened to involve multiple interfaces or not. Yes, there have been attempts. BSD has a concept of default interface. The default interface is used when the user did not specify the interface/ scope_id. Other OSs do different things. For example, Tru64 (to pick on a dead system) would try to find the right interface base on the preferences you could set up. But, in the end the whole thing is really utterly broken since no-one has truly implemented scoped address architecture for link-local addresses. The concept of the link is so closely tied to the 'interface' that I don't know anyone who has separated the two. Even so, it feels unpleasant for an application to deal with and I wonder if there is a way for a stack to deal with it on the application's behalf. I guess that might involve some sort of layer violation between neightbor discovery and routing (typing while I think about things I know little about...) Is there RFC chapter and verse I might read about routing with multiple link-local's on a system? See RFC 4007 for the concepts. You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). OK, I'll give that a quick try with netperf: [EMAIL PROTECTED] ~]# netperf -H 192.168.2.107 -c -C -i 30,3 -- -s 1M -S 1M -m 64K -H fe80::207:43ff:fe05:9d%2 TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to fe80::207:43ff:fe05:9d%2 (fe80::207:43ff:fe05:9d) port 0 AF_INET6 : +/-2.5% @ 99% conf. Cool - it establishes the data connection just fine. To further demonstrate my ignorance :) is that %n suffix something one might expect in most/all getaddrinfo()'s or is that unique to the one in Linux? This is becoming more generic. I believe HP-UX supports it (if the don't you should kick them :). -vlad - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: specifying scopid's for link-local IPv6 addrs
On Tue, 24 Jul 2007, Sridhar Samudrala wrote: On Tue, 2007-07-24 at 10:13 -0700, Rick Jones wrote: Rick, I don't see any way around this. For example, on one of my test systems, I have the following link local routes: chance% netstat -A inet6 -rn | grep fe80::/64 fe80::/64 :: U 25600 eth0 fe80::/64 :: U 25600 eth2 fe80::/64 :: U 25600 eth3 fe80::/64 :: U 25600 eth4 fe80::/64 :: U 25600 eth5 fe80::/64 :: U 25600 eth6 So if I want to run a link local test to fe80::202:b3ff:fed4:cd1, the system has no way to choose which is the correct interface to use for the test, and will give an error if the interface isn't specified. Yeah, I was wondering about that. I'm not sure if the attempts on those other OSes happened to involve multiple interfaces or not. Even so, it feels unpleasant for an application to deal with and I wonder if there is a way for a stack to deal with it on the application's behalf. I guess that might involve some sort of layer violation between neightbor discovery and routing (typing while I think about things I know little about...) Is there RFC chapter and verse I might read about routing with multiple link-local's on a system? You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). OK, I'll give that a quick try with netperf: [EMAIL PROTECTED] ~]# netperf -H 192.168.2.107 -c -C -i 30,3 -- -s 1M -S 1M -m 64K -H fe80::207:43ff:fe05:9d%2 We can even specify the interface name instead of the interface index link-local%ethX getaddrinfo() uses if_nametoindex() internally to get the index. Thanks Sridhar Cool! That's much easier and works great. :-) chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%eth6 1178.5468 MB / 10.02 sec = 986.3239 Mbps 13 %TX 15 %RX Still learn something new every day. Now if I just could remember it all when I needed it later. :-) -Thanks -Bill - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: specifying scopid's for link-local IPv6 addrs
On Mon, 23 Jul 2007, Rick Jones wrote: Folks - People running netperf have reported that they have trouble with IPv6 under Linux. Specifically, wereas the use of link-local IPv6 addresses just works in netperf under a number of other OSes they do not under Linux. I'm ass-u-me-ing 2.6 here, but not sure exactly which ones - I've seen it on a 2.6.18-based RHEL5. Some poking about and conversation has suggested that one has to set a sin6_scope_id in the sockaddr_in6. This needs to be an index of one of the interfaces in the system, which I presume means walking some additional structures. Is this a requirement which might be expected to remain in the future, or is it something which might just go away? That will have an effect on netperf future development. thanks, rick jones Rick, I don't see any way around this. For example, on one of my test systems, I have the following link local routes: chance% netstat -A inet6 -rn | grep fe80::/64 fe80::/64 :: U 25600 eth0 fe80::/64 :: U 25600 eth2 fe80::/64 :: U 25600 eth3 fe80::/64 :: U 25600 eth4 fe80::/64 :: U 25600 eth5 fe80::/64 :: U 25600 eth6 So if I want to run a link local test to fe80::202:b3ff:fed4:cd1, the system has no way to choose which is the correct interface to use for the test, and will give an error if the interface isn't specified. Here's an example of this with nuttcp: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1 nuttcp-t: Info: attempting to switch to deprecated classic mode nuttcp-t: Info: will use less reliable transmitter side statistics nuttcp-t: v5.5.5: Error: connect: Invalid argument errno=22 You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). -Bill - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: specifying scopid's for link-local IPv6 addrs
Rick, I don't see any way around this. For example, on one of my test systems, I have the following link local routes: chance% netstat -A inet6 -rn | grep fe80::/64 fe80::/64 :: U 25600 eth0 fe80::/64 :: U 25600 eth2 fe80::/64 :: U 25600 eth3 fe80::/64 :: U 25600 eth4 fe80::/64 :: U 25600 eth5 fe80::/64 :: U 25600 eth6 So if I want to run a link local test to fe80::202:b3ff:fed4:cd1, the system has no way to choose which is the correct interface to use for the test, and will give an error if the interface isn't specified. Yeah, I was wondering about that. I'm not sure if the attempts on those other OSes happened to involve multiple interfaces or not. Even so, it feels unpleasant for an application to deal with and I wonder if there is a way for a stack to deal with it on the application's behalf. I guess that might involve some sort of layer violation between neightbor discovery and routing (typing while I think about things I know little about...) Is there RFC chapter and verse I might read about routing with multiple link-local's on a system? You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). OK, I'll give that a quick try with netperf: [EMAIL PROTECTED] ~]# netperf -H 192.168.2.107 -c -C -i 30,3 -- -s 1M -S 1M -m 64K -H fe80::207:43ff:fe05:9d%2 TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to fe80::207:43ff:fe05:9d%2 (fe80::207:43ff:fe05:9d) port 0 AF_INET6 : +/-2.5% @ 99% conf. Cool - it establishes the data connection just fine. To further demonstrate my ignorance :) is that %n suffix something one might expect in most/all getaddrinfo()'s or is that unique to the one in Linux? rick jones - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: specifying scopid's for link-local IPv6 addrs
On Tue, 2007-07-24 at 10:13 -0700, Rick Jones wrote: Rick, I don't see any way around this. For example, on one of my test systems, I have the following link local routes: chance% netstat -A inet6 -rn | grep fe80::/64 fe80::/64 :: U 25600 eth0 fe80::/64 :: U 25600 eth2 fe80::/64 :: U 25600 eth3 fe80::/64 :: U 25600 eth4 fe80::/64 :: U 25600 eth5 fe80::/64 :: U 25600 eth6 So if I want to run a link local test to fe80::202:b3ff:fed4:cd1, the system has no way to choose which is the correct interface to use for the test, and will give an error if the interface isn't specified. Yeah, I was wondering about that. I'm not sure if the attempts on those other OSes happened to involve multiple interfaces or not. Even so, it feels unpleasant for an application to deal with and I wonder if there is a way for a stack to deal with it on the application's behalf. I guess that might involve some sort of layer violation between neightbor discovery and routing (typing while I think about things I know little about...) Is there RFC chapter and verse I might read about routing with multiple link-local's on a system? You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). OK, I'll give that a quick try with netperf: [EMAIL PROTECTED] ~]# netperf -H 192.168.2.107 -c -C -i 30,3 -- -s 1M -S 1M -m 64K -H fe80::207:43ff:fe05:9d%2 We can even specify the interface name instead of the interface index link-local%ethX getaddrinfo() uses if_nametoindex() internally to get the index. Thanks Sridhar TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to fe80::207:43ff:fe05:9d%2 (fe80::207:43ff:fe05:9d) port 0 AF_INET6 : +/-2.5% @ 99% conf. Cool - it establishes the data connection just fine. To further demonstrate my ignorance :) is that %n suffix something one might expect in most/all getaddrinfo()'s or is that unique to the one in Linux? rick jones - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: specifying scopid's for link-local IPv6 addrs
You must explicitly specify the desired interface. For example, on my test system, the correct interface is eth6 which is interface 8 (lo eth0 eth1 eth2 ... eth5 eth6). Here is an example nuttcp test specifying interface 8: chance% nuttcp -P5100 fe80::202:b3ff:fed4:cd1%8 1178.5809 MB / 10.02 sec = 986.2728 Mbps 12 %TX 15 %RX nuttcp uses getaddrinfo() which parses the %ifindex field, and then copies the sin6_scope_id from the res structure to the server's sockaddr_in6 structure before initiating the connect(). OK, I'll give that a quick try with netperf: [EMAIL PROTECTED] ~]# netperf -H 192.168.2.107 -c -C -i 30,3 -- -s 1M -S 1M -m 64K -H fe80::207:43ff:fe05:9d%2 TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to fe80::207:43ff:fe05:9d%2 (fe80::207:43ff:fe05:9d) port 0 AF_INET6 : +/-2.5% @ 99% conf. Cool - it establishes the data connection just fine. Well, I spoke too soon - while it got me past my EINVAL, the connection establishement timed-out. Either I picked the wrong value for n, or I may yet need to make some tweaks to netperf. rick jones - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
specifying scopid's for link-local IPv6 addrs
Folks - People running netperf have reported that they have trouble with IPv6 under Linux. Specifically, wereas the use of link-local IPv6 addresses just works in netperf under a number of other OSes they do not under Linux. I'm ass-u-me-ing 2.6 here, but not sure exactly which ones - I've seen it on a 2.6.18-based RHEL5. Some poking about and conversation has suggested that one has to set a sin6_scope_id in the sockaddr_in6. This needs to be an index of one of the interfaces in the system, which I presume means walking some additional structures. Is this a requirement which might be expected to remain in the future, or is it something which might just go away? That will have an effect on netperf future development. thanks, rick jones - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
