Tickets - Tunnel server responding with protocol 41 unreachable :: SixXS

Ticket ID: SIXXS #530896
Ticket Status: Resolved

PoP: demuc02 - M-net Telekommunikations GmbH (Muenchen)

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Monday, 04 June 2007 11:21:14

aiccu test fails on trying to ping gw-74.muc-02.de.sixxs.net. tcpdump output follows: 11:11:33.953427 IP 83.171.187.199 > 62.245.150.2: IP6 2001:a60:f000:49::2 > 2001:a60:f000:49::1: ICMP6, echo request, seq 1, length 64 0x0000: 4500 007c 0000 4000 4029 55ef 53ab bbc7 E..|..@.@)U.S... 0x0010: 3ef5 9602 6000 0000 0040 3a40 2001 0a60 >...`....@:@...` 0x0020: f000 0049 0000 0000 0000 0002 2001 0a60 ...I...........` 0x0030: f000 0049 0000 0000 0000 0001 8000 d200 ...I............ 0x0040: ab7d 0001 45d7 6346 2a8c 0e00 0809 0a0b .}..E.cF*....... 0x0050: 0c0d 0e0f 1011 1213 1415 1617 1819 1a1b ................ 0x0060: 1c1d 1e1f 2021 2223 2425 2627 2829 2a2b .....!"#$%&'()*+ 0x0070: 2c2d 2e2f 3031 3233 3435 3637 ,-./01234567 11:11:33.963281 IP 62.245.150.2 > 83.171.187.199: ICMP 62.245.150.2 protocol 41 unreachable, length 132 0x0000: 45c0 0098 27bc 0000 3d01 707f 3ef5 9602 E...'...=.p.>... 0x0010: 53ab bbc7 0302 62f7 0000 0000 4500 007c S.....b.....E..| 0x0020: 0000 4000 3b29 5aef 53ab bbc7 3ef5 9602 ..@.;)Z.S...>... 0x0030: 6000 0000 0040 3a40 2001 0a60 f000 0049 `....@:@...`...I 0x0040: 0000 0000 0000 0002 2001 0a60 f000 0049 ...........`...I 0x0050: 0000 0000 0000 0001 8000 d200 ab7d 0001 .............}.. 0x0060: 45d7 6346 2a8c 0e00 0809 0a0b 0c0d 0e0f E.cF*........... 0x0070: 1011 1213 1415 1617 1819 1a1b 1c1d 1e1f ................ 0x0080: 2021 2223 2425 2627 2829 2a2b 2c2d 2e2f .!"#$%&'()*+,-./ 0x0090: 3031 3233 3435 3637 01234567 Running AICCU 2007.01.15-console-linux by Jeroen Massar karoka:~# uname -a Linux karoka 2.6.18-4-amd64 #1 SMP Thu May 10 01:01:58 UTC 2007 x86_64 GNU/Linuxkaroka:~# traceroute 62.245.150.2 traceroute to 62.245.150.2 (62.245.150.2), 30 hops max, 40 byte packets 1 BBRAS-SR-ERX2-DEFAULT.nefkom.de (212.114.214.8) 11.192 ms 4.845 ms 8.253 ms 2 gi1-9.r2.nue2.m-online.net (212.18.6.237) 5.607 ms 4.234 ms 7.739 ms 3 te1-3.r2.muc2.m-online.net (212.18.6.61) 10.834 ms 9.623 ms 9.362 ms 4 88.217.194.26 (88.217.194.26) 10.766 ms 7.640 ms 7.370 ms 5 svr16.m-online.net (62.245.150.197) 7.057 ms 7.244 ms 7.086 ms 6 demuc2.sixxs.net (62.245.150.2) 7.126 ms 7.507 ms 7.080 ms karoka:~# ifconfig eth0 Link encap:Ethernet HWaddr 00:50:8D:7D:66:0F inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: 2001:a60:f039::/64 Scope:Global inet6 addr: fe80::250:8dff:fe7d:660f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1492 Metric:1 RX packets:14477289 errors:0 dropped:0 overruns:0 frame:0 TX packets:12826100 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:2708472685 (2.5 GiB) TX bytes:3394165346 (3.1 GiB) Interrupt:201 eth1 Link encap:Ethernet HWaddr 00:0E:2E:9C:C4:6C inet6 addr: fe80::20e:2eff:fe9c:c46c/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:4375725 errors:0 dropped:0 overruns:0 frame:0 TX packets:3669956 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1578796306 (1.4 GiB) TX bytes:1161844577 (1.0 GiB) Interrupt:209 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:1046513 errors:0 dropped:0 overruns:0 frame:0 TX packets:1046513 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:483076993 (460.6 MiB) TX bytes:483076993 (460.6 MiB) ppp0 Link encap:Point-to-Point Protocol inet addr:83.171.187.199 P-t-P:212.114.214.8 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1 RX packets:36230 errors:0 dropped:0 overruns:0 frame:0 TX packets:35242 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:3 RX bytes:4727874 (4.5 MiB) TX bytes:6595843 (6.2 MiB) sixxs Link encap:IPv6-in-IPv4 inet6 addr: 2001:a60:f000:49::2/64 Scope:Global inet6 addr: fe80::a4f:87a/64 Scope:Link inet6 addr: fe80::53ab:bbc7/64 Scope:Link inet6 addr: fe80::c0a8:1/64 Scope:Link UP POINTOPOINT RUNNING NOARP MTU:1472 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:10 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:1216 (1.1 KiB) tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:10.79.8.122 P-t-P:10.79.8.121 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:8558 errors:0 dropped:0 overruns:0 frame:0 TX packets:7079 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:704793 (688.2 KiB) TX bytes:1806808 (1.7 MiB) karoka:~# ip -4 route 212.114.214.8 dev ppp0 proto kernel scope link src 83.171.187.199 10.79.8.121 dev tun0 proto kernel scope link src 10.79.8.122 131.188.12.11 dev ppp0 scope link 10.79.8.1 via 10.79.8.121 dev tun0 192.168.7.0/24 via 10.79.8.121 dev tun0 192.44.86.0/24 via 10.79.8.121 dev tun0 192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.1 131.188.0.0/16 via 10.79.8.121 dev tun0 172.16.0.0/16 via 10.79.8.121 dev tun0 172.17.0.0/16 via 10.79.8.121 dev tun0 141.67.0.0/16 via 10.79.8.121 dev tun0 10.0.0.0/8 via 10.79.8.121 dev tun0 default dev ppp0 scope link karoka:~# ip -6 route 2001:a60:f000:49::/64 via :: dev sixxs metric 256 expires 21333281sec mtu 1472 advmss 1412 hoplimit 4294967295 2001:a60:f039::/64 dev eth0 metric 256 expires 20685162sec mtu 1492 advmss 1432 hoplimit 4294967295 unreachable 2001:a60:f039::/48 dev lo metric 1024 expires 19446319sec error -101 mtu 16436 advmss 16376 hoplimit 4294967295 fe80::/64 dev eth1 metric 256 expires 19446330sec mtu 1500 advmss 1440 hoplimit 4294967295 fe80::/64 dev eth0 metric 256 expires 20685152sec mtu 1492 advmss 1432 hoplimit 4294967295 fe80::/64 via :: dev sixxs metric 256 expires 21333281sec mtu 1472 advmss 1412 hoplimit 4294967295 ff00::/8 dev eth1 metric 256 expires 19446330sec mtu 1500 advmss 1440 hoplimit 4294967295 ff00::/8 dev eth0 metric 256 expires 20685152sec mtu 1492 advmss 1432 hoplimit 4294967295 ff00::/8 dev sixxs metric 256 expires 21333281sec mtu 1472 advmss 1412 hoplimit 4294967295 default via 2001:a60:f000:49::1 dev sixxs metric 1024 expires 21333281sec mtu 1472 advmss 1412 hoplimit 4294967295 karoka:~# ntpq -c peers remote refid st t when poll reach delay offset jitter ============================================================================== ntp1.ipv6.lrz-m .PPS. 1 u 12h 1024 0 33.178 -0.003 0.000 chime5.surfnet. .PPS. 1 u 12h 1024 0 54.562 -4.181 0.000 *ntp2-rz.rrze.un .GPS. 1 u 595 1024 377 23.447 -0.121 0.229 tt01.ripe.net .GPS. 1 u 12h 1024 0 33.914 0.901 0.000 192.168.0.255 .BCST. 16 u - 64 0 0.000 0.000 0.001 Problem with NIC Handle RKK1-SIXXS, tunnel ID T11398 No IPv4/6 firewall rules active

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Monday, 04 June 2007 14:11:46

Confirmed, SSH is down as well. I've contacted the M-net operators to reboot the box, looks like a hickup.

State change: confirmed Locked

Jeroen Massar SixXS Staff

on Monday, 04 June 2007 14:15:36

The state of this ticket has been changed to confirmed

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Monday, 04 June 2007 17:36:12

System is back on. During an upgrade of the Debian system on this machine the underlying virtualization mechanism (User Mode Linux) broke, apparently due to some incompatibilities between UML and the libc6 in Debian testing. This led to slowly degrading service, as new processes could not be started (so e.g. heartbeat tunnels worked until you changed your IPv4 address). The operators used this opportunity to migrate the VM to a Xen instance. Due to that it should be even faster now.

State change: resolved Locked

Jeroen Massar SixXS Staff

on Monday, 04 June 2007 17:50:43

The state of this ticket has been changed to resolved

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Tuesday, 03 March 2009 13:59:37

I have read and followed the "Reporting Problems" section on the Contact page and am providing the following details for this report based on the list of items stated there: This problem seems to have come back for me, the tunnel server again responds with protocol 41 unreachable: 13:49:10.807139 IP ppp-88-217-107-82.dynamic.mnet-online.de > 62.245.150.2: IP6 cl-74.muc-02.de.sixxs.net.39021 > noc.sixxs.net.www: S 2575528201:2575528201(0) win 5648 <[|tcp]> 13:49:10.815336 IP 62.245.150.2 > ppp-88-217-107-82.dynamic.mnet-online.de: ICMP 62.245.150.2 protocol 41 port 0 unreachable, length 108

Tunnel server responding with protocol 41 unreachable

Jeroen Massar SixXS Staff

on Tuesday, 03 March 2009 14:04:36

As you have a heartbeat tunnel, are you sending proper heartbeats?

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Tuesday, 03 March 2009 14:22:01

AICCU has been running since Feb 15th without any problems up to this point. I am not entirely sure how to check it is heartbeating properly. That being said, I am glad to report that the problem has disappeared as of five minutes ago. So either it was a very temporary outage, or whatever you did to diagnose the problem already fixed it. In any case, thank you!

Tunnel server responding with protocol 41 unreachable

Jeroen Massar SixXS Staff

on Tuesday, 03 March 2009 14:34:30

AICCU only checks if your clock is okay at startup, not after that. Thus if it is running for a long time it won't notice a time discrepancy. As such check that your clock is properly NTP synced and of course also in the correct timezone.

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Tuesday, 03 March 2009 14:48:59

I don't think time sync was the issue here. This was my NTP status during the problem: karoka:~> ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================== -ntp1.ipv6.lrz-m .PPS. 1 u 88m 512 340 25.721 -0.526 0.048 -galadriel.rrze. .GPS. 1 u 70m 512 340 26.365 -0.753 2.518 *ntp1.rrze.uni-e .DCFp. 1 u 110 512 377 31.903 0.527 0.096 +tt12.ripe.Net .GPS. 1 u 88m 512 340 10.035 0.682 0.037 +2003:0:8:ff::ff .GPS. 1 u 95m 512 300 10.332 0.611 0.155 After the outage: karoka:~> ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================== -ntp1.ipv6.lrz-m .PPS. 1 u 424 512 13 25.558 -0.460 9.253 +galadriel.rrze. .GPS. 1 u 375 512 13 21.690 0.754 0.571 *ntp1.rrze.uni-e .DCFp. 1 u 385 512 377 32.092 0.409 0.273 +tt12.ripe.Net .GPS. 1 u 445 512 13 9.485 0.932 0.052 2003:0:8:ff::ff .GPS. 1 u 343 512 13 10.183 0.953 0.074 And for reference, this is my offset to demuc02: 3 Mar 14:43:21 ntpdate[16204]: adjust time server 62.245.150.2 offset 0.171188 sec Seems like demuc02 and my machine are about 170ms off from each other, so nowhere near the 120 seconds noted in the Heartbeat documentation.

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Monday, 08 June 2009 09:06:14

I have read and followed the "Reporting Problems" section on the Contact page and am providing the following details for this report based on the list of items stated there: This problem has come back for me as of 90 minutes ago. Time sync on my system is ok, the system is synchronized to a NTP server at my university. AICCU restarts ok, but fails at test trying to ping gw-74.muc-02.de.sixxs.net: 08:59:46.594238 IP ppp-88-217-105-245.dynamic.mnet-online.de > 62.245.150.2: IP6 cl-74.muc-02.de.sixxs.net > gw-74.muc-02.de.sixxs.net: ICMP6, echo request, seq 1, length 64 08:59:46.602397 IP 62.245.150.2 > ppp-88-217-105-245.dynamic.mnet-online.de: ICMP 62.245.150.2 protocol 41 port 0 unreachable, length 132 Unfortunately I can't check my time offset to the tunnel server, as NTP seems to be disabled (for public access?) now. Anyways, here's the NTP peers output on my end as diagnostics as well: karoka:~> ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================== -ntp1.ipv6.lrz-m .PPS. 1 u 84m 1024 360 25.247 -2.080 0.128 +galadriel.rrze. .GPS. 1 u 80m 1024 360 20.821 -1.012 0.048 -ntp1.rrze.uni-e 129.143.2.23 2 u 971 1024 377 31.729 -0.577 0.114 *tt12.ripe.Net .GPS. 1 u 84m 1024 360 9.170 -0.666 0.118 +2003:0:8:ff::ff .GPS. 1 u 94m 1024 340 9.982 -0.641 0.027 Thanks for looking into it, Roland

Tunnel server responding with protocol 41 unreachable

Shadow Hawkins on Monday, 08 June 2009 10:29:55

Update: The problem disappeared again, tunnel working as usual.

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