big german provider "Deutsche Telekom" has started blocking access to their SIP servers
Hi a big German provider "Deutsche Telekom" has started blocking access (at TCP layer) to their SIP servers in February 2026. That means running a middle tor on this provider line results in a non-functional provider SIP service. You have to choose between running a middle tor or a working provider SIP service.
On 14.02.2026 13:50 iji--- via tor-relays <tor-relays@lists.torproject.org> wrote:
a big German provider "Deutsche Telekom" has started blocking access (at TCP layer) to their SIP servers in February 2026. That means running a middle tor on this provider line results in a non-functional provider SIP service. You have to choose between running a middle tor or a working provider SIP service.
Is UDP SIP also affected? What does their support say? -- kind regards Marco Send spam to abfall1771073455@stinkedores.dorfdsl.de
So that means Deutsche Telekom monitors Internet traffic (or at least the Tor directory, which contains all the nodes) and detects when a Tor node is being operated. And if that is the case, TCP access to the SIP servers is blocked? Or have I misunderstood something here? On Sat, 14 Feb 2026 13:50:55 -0000 iji--- via tor-relays <tor-relays@lists.torproject.org> wrote:
Hi a big German provider "Deutsche Telekom" has started blocking access (at TCP layer) to their SIP servers in February 2026. That means running a middle tor on this provider line results in a non-functional provider SIP service. You have to choose between running a middle tor or a working provider SIP service. _______________________________________________ tor-relays mailing list -- tor-relays@lists.torproject.org To unsubscribe send an email to tor-relays-leave@lists.torproject.org
-- Marek Küthe m.k@mk16.de er/ihm he/him
They probably use this blocklist, as do many websites, especially banks and email providers. https://mxtoolbox.com/problem/blacklist/dan-tor Thismeanstheydon'thavetomonitorinternettrafficthemselves. Am 16.02.26 um 23:10 schrieb Marek Küthe via tor-relays:
So that means Deutsche Telekom monitors Internet traffic (or at least the Tor directory, which contains all the nodes) and detects when a Tor node is being operated. And if that is the case, TCP access to the SIP servers is blocked? Or have I misunderstood something here?
On Sat, 14 Feb 2026 13:50:55 -0000 iji--- via tor-relays<tor-relays@lists.torproject.org> wrote:
Hi a big German provider "Deutsche Telekom" has started blocking access (at TCP layer) to their SIP servers in February 2026. That means running a middle tor on this provider line results in a non-functional provider SIP service. You have to choose between running a middle tor or a working provider SIP service. _______________________________________________ tor-relays mailing list --tor-relays@lists.torproject.org To unsubscribe send an email totor-relays-leave@lists.torproject.org
_______________________________________________ tor-relays mailing list --tor-relays@lists.torproject.org To unsubscribe send an email totor-relays-leave@lists.torproject.org
-- PGP Key ID: 29D319F8
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hello. Juergen Lanzki wrote:
They probably use this blocklist, as do many websites, especially banks and email providers.
Has anyone in the industry tried contacting mxtoolbox and getting them to stop using the DAN list? Obviously that Dan guy will never stop listing non-exits because he personally hates Tor, but mxtoolbox could use Tor Project's own blacklist. Plenty of reputable blacklist providers, while not "Tor-friendly" per se, do understand that exit operators are not responsible for the traffic going through and, importantly, that non-exits are harmless (for example, IPInfo does this). I almost lost a relay because the hosting provider got spooked that I suddenly got their IP on a "blacklist" and had a hard time understanding that mxtoolbox including DAN's shit does not mean I was sending spam. Regards, forest -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQQtr8ZXhq/o01Qf/pow+TRLM+X4xgUCaZY//wAKCRAw+TRLM+X4 xjhVAQDN0a49OuTc/W99mAUu6Ux1ro8CZWpbCnQlHGcJdhKDnAEA2FWqazCACRdy 19K+UUiVpP4cAmN0KWV6HB75DfIoCA4= =6g7j -----END PGP SIGNATURE-----
I get this on my exit: "Auto-discovered IPv6 address [2a00:da00:f460:f800::1]:443 has not been found reachable" As far as firewall is concerned it is reachable. I can see the control port web page using Ipv6 address, and SSH into my odd SSH port using IPv6. IPv6 is working and routing 100 % correctly. IPv6 exits seem quite popular. ORport [2axx:dxxx:f460:f809::2]:443 Somehow Tor does not see it, well it sees it to test the port but then says not reachable, but no access within TOR? (Linux 6.8.0-10...) Tor 0.4.9.5 (recommended) Gerry
Am 22.02.2026 um 17:39:29 Uhr schrieb DocGerry via tor-relays:
As far as firewall is concerned it is reachable. I can see the control port web page using Ipv6 address, and SSH into my odd SSH port using IPv6. IPv6 is working and routing 100 % correctly. IPv6 exits seem quite popular.
ORport [2axx:dxxx:f460:f809::2]:443
Somehow Tor does not see it, well it sees it to test the port but then says not reachable, but no access within TOR?
I've tried and I can access it. Please post your fingerprint, so we can check the consensus. -- kind regards Marco Send unsolicited bulk mail to 1771778369muell@cartoonies.org
Thanks Marco looking into this 51AE5656C81CD417479253A6363A123A007A2233 Consensus Weight 55000 Gerry -----Original Message----- From: Marco Moock via tor-relays <tor-relays@lists.torproject.org> Sent: 22 February 2026 19:28 To: tor-relays@lists.torproject.org Cc: Marco Moock <mm@dorfdsl.de> Subject: [tor-relays] Re: IPV6 Reachable ? Am 22.02.2026 um 17:39:29 Uhr schrieb DocGerry via tor-relays:
As far as firewall is concerned it is reachable. I can see the control port web page using Ipv6 address, and SSH into my odd SSH port using IPv6. IPv6 is working and routing 100 % correctly. IPv6 exits seem quite popular.
ORport [2axx:dxxx:f460:f809::2]:443
Somehow Tor does not see it, well it sees it to test the port but then says not reachable, but no access within TOR?
I've tried and I can access it. Please post your fingerprint, so we can check the consensus. -- kind regards Marco Send unsolicited bulk mail to 1771778369muell@cartoonies.org
Am 22.02.2026 um 19:54:29 Uhr schrieb DocGerry via tor-relays:
51AE5656C81CD417479253A6363A123A007A2233
https://consensus-health.torproject.org/ Doesn't seem to check IPv6 at all. Please restart (fully restart, not reload) the tor software and check if reachability changes. AFAIK, I can reach it, I assume a restart will fix that. If it still says it cannot reach it, use tcpdump and monitor all incoming IPv6 traffic to this address/port. Then check if any packages go in and out. -- kind regards Marco Send unsolicited bulk mail to 1771786469muell@cartoonies.org
Restarted Nyx /var/log/notices.log has not commented on ipv6 as yet, perhaps it won't if working. Ipv4 reachable of course. tcpdump -i ens6 -nn ip6 and dst port 443 and inbound shows IPv6 activity. Thanks for speedy replies Gerry -----Original Message----- From: Marco Moock via tor-relays <tor-relays@lists.torproject.org> Sent: 22 February 2026 20:15 To: tor-relays@lists.torproject.org Cc: Marco Moock <mm@dorfdsl.de> Subject: [tor-relays] Re: IPV6 Reachable ? Am 22.02.2026 um 19:54:29 Uhr schrieb DocGerry via tor-relays:
51AE5656C81CD417479253A6363A123A007A2233
https://consensus-health.torproject.org/ Doesn't seem to check IPv6 at all. Please restart (fully restart, not reload) the tor software and check if reachability changes. AFAIK, I can reach it, I assume a restart will fix that. If it still says it cannot reach it, use tcpdump and monitor all incoming IPv6 traffic to this address/port. Then check if any packages go in and out. -- kind regards Marco Send unsolicited bulk mail to 1771786469muell@cartoonies.org
"21:28:55 [NOTICE] Unable to find IPv6 address for ORPort 443. You might want to specify IPv4Only to it or set an explicit address or set Address. [62 similar message(s) suppressed in last 3600 seconds]" All a bit odd root@uk:/var/log/tor# tcpdump -i ens6 -nn ip6 and dst port 443 and inbound tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on ens6, link-type EN10MB (Ethernet), snapshot length 262144 bytes 21:38:23.865226 IP6 26xx:840:48YZ:5cxx:a511:e404:2d48:c9fa.47405 > 2axx:da00:f4xx:f8xx::1.443: Flags [S], seq 1001287751, win 65535, options [mss 1440,sackOK,TS val 3347902614 ecr 0,nop,wscale 10], length 0 etc Gerry -----Original Message----- From: gerard@bulger.co.uk <gerard@bulger.co.uk> Sent: 22 February 2026 20:55 To: 'support and questions about running Tor relays (exit, non-exit, bridge)' <tor-relays@lists.torproject.org> Cc: 'Marco Moock' <mm@dorfdsl.de> Subject: RE: [tor-relays] Re: IPV6 Reachable ? Restarted Nyx /var/log/notices.log has not commented on ipv6 as yet, perhaps it won't if working. Ipv4 reachable of course. tcpdump -i ens6 -nn ip6 and dst port 443 and inbound shows IPv6 activity. Thanks for speedy replies Gerry -----Original Message----- From: Marco Moock via tor-relays <tor-relays@lists.torproject.org> Sent: 22 February 2026 20:15 To: tor-relays@lists.torproject.org Cc: Marco Moock <mm@dorfdsl.de> Subject: [tor-relays] Re: IPV6 Reachable ? Am 22.02.2026 um 19:54:29 Uhr schrieb DocGerry via tor-relays:
51AE5656C81CD417479253A6363A123A007A2233
https://consensus-health.torproject.org/ Doesn't seem to check IPv6 at all. Please restart (fully restart, not reload) the tor software and check if reachability changes. AFAIK, I can reach it, I assume a restart will fix that. If it still says it cannot reach it, use tcpdump and monitor all incoming IPv6 traffic to this address/port. Then check if any packages go in and out. -- kind regards Marco Send unsolicited bulk mail to 1771786469muell@cartoonies.org
On 22.02.2026 21:41 <gerard@bulger.co.uk> wrote:
"21:28:55 [NOTICE] Unable to find IPv6 address for ORPort 443. You might want to specify IPv4Only to it or set an explicit address or set Address. [62 similar message(s) suppressed in last 3600 seconds]"
grep ORPort /etc/tor/torrc #or another location, depending on the OS Check that this address is still assigned. -- kind regards Marco Send spam to abfall1771792897@stinkedores.dorfdsl.de
And either don't understand the difference between all tor nodes and exit nodes. Or can't be bothered to find out. On 2/17/2026 1:10 AM, Juergen Lanzki via tor-relays wrote:
They probably use this blocklist, as do many websites, especially banks and email providers.
https://mxtoolbox.com/problem/blacklist/dan-tor
Thismeanstheydon'thavetomonitorinternettrafficthemselves.
Am 16.02.26 um 23:10 schrieb Marek Küthe via tor-relays:
So that means Deutsche Telekom monitors Internet traffic (or at least the Tor directory, which contains all the nodes) and detects when a Tor node is being operated. And if that is the case, TCP access to the SIP servers is blocked? Or have I misunderstood something here?
On Sat, 14 Feb 2026 13:50:55 -0000 iji--- via tor-relays<tor-relays@lists.torproject.org> wrote:
Hi a big German provider "Deutsche Telekom" has started blocking access (at TCP layer) to their SIP servers in February 2026. That means running a middle tor on this provider line results in a non-functional provider SIP service. You have to choose between running a middle tor or a working provider SIP service. _______________________________________________ tor-relays mailing list --tor-relays@lists.torproject.org To unsubscribe send an email totor-relays-leave@lists.torproject.org
_______________________________________________ tor-relays mailing list --tor-relays@lists.torproject.org To unsubscribe send an email totor-relays-leave@lists.torproject.org
-- PGP Key ID: 29D319F8
_______________________________________________ tor-relays mailing list --tor-relays@lists.torproject.org To unsubscribe send an email totor-relays-leave@lists.torproject.org
* forest-relay-contact--- via tor-relays <tor-relays@lists.torproject.org> wrote:
Has anyone in the industry tried contacting mxtoolbox and getting them to stop using the DAN list?
Someone much wiser than me once said something like this: "When you are hit by arrows, nothing changes unless you deal with the archer." So there you go, have a chat with that DAN list guy... In essence, if theres a blocklist, folks will use it for convenience. In case if you haven't already noticed, convenience tends to win when it comes to humans, by a large margin. Hth, Markus
I get this on my exit: "Auto-discovered IPv6 address [2a00:da00:f460:f800::1]:443 has not been found reachable" As far as firewall is concerned it is reachable. I can see the control port web page on Ipv6 address, and SSH into my odd SSH port using IPv6. IPv6 is working and routing 100 % correctly. IPv6 exits seem quite popular. ORport[2axx:dxxx:f460:f809::2]:443 Somehow Tor does not see it, well sees it to test the port but then says not reachable, so no access within TOR? (Linux 6.8.0-10...) Tor 0.4.9.5 (recommended) Gerry -----Original Message----- From: forest-relay-contact--- via tor-relays <tor-relays@lists.torproject.org> Sent: 18 February 2026 22:41 To: tor-relays@lists.torproject.org Cc: forest-relay-contact@cryptolab.net Subject: [tor-relays] Re: big german provider "Deutsche Telekom" has started blocking access to their SIP servers -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hello. Juergen Lanzki wrote:
They probably use this blocklist, as do many websites, especially banks and email providers.
Has anyone in the industry tried contacting mxtoolbox and getting them to stop using the DAN list? Obviously that Dan guy will never stop listing non-exits because he personally hates Tor, but mxtoolbox could use Tor Project's own blacklist. Plenty of reputable blacklist providers, while not "Tor-friendly" per se, do understand that exit operators are not responsible for the traffic going through and, importantly, that non-exits are harmless (for example, IPInfo does this). I almost lost a relay because the hosting provider got spooked that I suddenly got their IP on a "blacklist" and had a hard time understanding that mxtoolbox including DAN's shit does not mean I was sending spam. Regards, forest -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQQtr8ZXhq/o01Qf/pow+TRLM+X4xgUCaZY//wAKCRAw+TRLM+X4 xjhVAQDN0a49OuTc/W99mAUu6Ux1ro8CZWpbCnQlHGcJdhKDnAEA2FWqazCACRdy 19K+UUiVpP4cAmN0KWV6HB75DfIoCA4= =6g7j -----END PGP SIGNATURE----- _______________________________________________ tor-relays mailing list -- tor-relays@lists.torproject.org To unsubscribe send an email to tor-relays-leave@lists.torproject.org
Auto-discovered IPv6 address [2a00:da00:f460:f800::1]:443 has not been found reachable. However, IPv4 address is reachable Yet is says 09:36:45 [NOTICE] Heartbeat: Tor's uptime is 10:21 hours, with 14231 circuits open. I've sent 602.28 GB and received 594.50 GB. I've received 64725 connections on IPv4 and 1021 on IPv6. I've made 2301709 connections with IPv4 and 437304 with IPv6. [1 duplicate hidden] Seems working fine. Gerry -----Original Message----- From: DocGerry via tor-relays <tor-relays@lists.torproject.org> Sent: 22 February 2026 21:42 To: 'support and questions about running Tor relays (exit, non-exit, bridge)' <tor-relays@lists.torproject.org> Cc: 'Marco Moock' <mm@dorfdsl.de>; gerard@bulger.co.uk Subject: [tor-relays] Re: IPV6 Reachable ? "21:28:55 [NOTICE] Unable to find IPv6 address for ORPort 443. You might want to specify IPv4Only to it or set an explicit address or set Address. [62 similar message(s) suppressed in last 3600 seconds]" All a bit odd root@uk:/var/log/tor# tcpdump -i ens6 -nn ip6 and dst port 443 and inbound tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on ens6, link-type EN10MB (Ethernet), snapshot length 262144 bytes 21:38:23.865226 IP6 26xx:840:48YZ:5cxx:a511:e404:2d48:c9fa.47405 > 2axx:da00:f4xx:f8xx::1.443: Flags [S], seq 1001287751, win 65535, options [mss 1440,sackOK,TS val 3347902614 ecr 0,nop,wscale 10], length 0 etc Gerry -----Original Message----- From: gerard@bulger.co.uk <gerard@bulger.co.uk> Sent: 22 February 2026 20:55 To: 'support and questions about running Tor relays (exit, non-exit, bridge)' <tor-relays@lists.torproject.org> Cc: 'Marco Moock' <mm@dorfdsl.de> Subject: RE: [tor-relays] Re: IPV6 Reachable ? Restarted Nyx /var/log/notices.log has not commented on ipv6 as yet, perhaps it won't if working. Ipv4 reachable of course. tcpdump -i ens6 -nn ip6 and dst port 443 and inbound shows IPv6 activity. Thanks for speedy replies Gerry -----Original Message----- From: Marco Moock via tor-relays <tor-relays@lists.torproject.org> Sent: 22 February 2026 20:15 To: tor-relays@lists.torproject.org Cc: Marco Moock <mm@dorfdsl.de> Subject: [tor-relays] Re: IPV6 Reachable ? Am 22.02.2026 um 19:54:29 Uhr schrieb DocGerry via tor-relays:
51AE5656C81CD417479253A6363A123A007A2233
https://consensus-health.torproject.org/ Doesn't seem to check IPv6 at all. Please restart (fully restart, not reload) the tor software and check if reachability changes. AFAIK, I can reach it, I assume a restart will fix that. If it still says it cannot reach it, use tcpdump and monitor all incoming IPv6 traffic to this address/port. Then check if any packages go in and out. -- kind regards Marco Send unsolicited bulk mail to 1771786469muell@cartoonies.org _______________________________________________ tor-relays mailing list -- tor-relays@lists.torproject.org To unsubscribe send an email to tor-relays-leave@lists.torproject.org
On 23.02.2026 11:14 <gerard@bulger.co.uk> wrote:
Auto-discovered IPv6 address [2a00:da00:f460:f800::1]:443 has not been found reachable. However, IPv4 address is reachable
Yet is says
09:36:45 [NOTICE] Heartbeat: Tor's uptime is 10:21 hours, with 14231 circuits open. I've sent 602.28 GB and received 594.50 GB. I've received 64725 connections on IPv4 and 1021 on IPv6. I've made 2301709 connections with IPv4 and 437304 with IPv6. [1 duplicate hidden]
Does that issue still exists with this message? -- kind regards Marco Send spam to abfall1771841676@stinkedores.dorfdsl.de
On 22.02.2026 15:23 DocGerry via tor-relays <tor-relays@lists.torproject.org> wrote:
As far as firewall is concerned it is reachable. I can see the control port web page on Ipv6 address, and SSH into my odd SSH port using IPv6. IPv6 is working and routing 100 % correctly. IPv6 exits seem quite popular.
Do not expose the control port to the public. You only need to expose the ORPort. Do you use any NAT with IPv6? -- kind regards Marco Send spam to abfall1771770212@stinkedores.dorfdsl.de
participants (8)
-
Eddie -
forest-relay-contact@cryptolab.net -
gerard@bulger.co.uk -
iji@gmx.net -
Juergen Lanzki -
Marco Moock -
Marek Küthe -
Markus Reichelt