AS31382 - CANCOM-Austria-IT CANCOM Austria AGPI/PARFC 4890 ✗RPKI ✓ 2/2ASPA -

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AS overview

Test target: 2a04:c7c0::1 · static prefix probe · address space: mixed · prefixes announced: 2

prefix(es): 2a04:c7c0::/29, 2001:67c:2248::/48

Targets & per-vantage-point probe results (1 target(s) across 7 vantage point(s))

Source codes (hover any badge for full description): CUR=curated · NS/SOA/MX=DNS records · SPF=SPF TXT · DRV=holder-derived (www, ns1, mail, gw, …) · ATL=RIPE Atlas · PDB=PeeringDB · WHOIS=RIPE whois · RDAP=RIPE RDAP · HIT=IPv6 Hitlist · RTR=in-prefix path hop (router) · PRB=static prefix probe · SYN=synthetic prefix::1 fallback

Target IP / hostnameSourceSRB host (SOX, Belgrade)DE host (Berlin)DE host (Düsseldorf)NL host (go6lab)ITA host (Karsolink)SLO host (6connect)SLO host (T-2)
ping1500B:80:443reachedping1500B:80:443reachedping1500B:80:443reachedping1500B:80:443reachedping1500B:80:443reachedping1500B:80:443reachedping1500B:80:443reached
2a04:c7c0::1prbrefusedrefused-refusedrefusedrefusedrefused-??refusedrefusedrefusedrefusedrefusedrefused

VIX / AAIX / SAIX / TIROL-IX / ERA-IX peering

Not an VIX / AAIX / SAIX / TIROL-IX / ERA-IX member, but our traceroute path crosses the VIX / AAIX / SAIX / TIROL-IX / ERA-IX LAN from SLO host (T-2) - reached via an VIX / AAIX / SAIX / TIROL-IX / ERA-IX-resident transit operator.

RPKI & ASPA

2 of 2 prefix(es) covered by a valid ROA.

PrefixRPKI stateReasonCovering VRP(s)
2a04:c7c0::/29✓ validmatched VRP (correct origin, length within maxLength)AS31382 /29 maxLen 29 (ripe)
2001:67c:2248::/48✓ validmatched VRP (correct origin, length within maxLength)AS31382 /48 maxLen 48 (ripe)

Random-IP probe (yarrp) into the AS' prefixes

We probed 70 arbitrary IPv6 address(es) inside AS31382's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a01:190:100a:4::2 at hop 16 - that router answers ICMPv6 Echo. This is not in AS31382's announced prefix; operationally it's the AS-edge / peering interface (often on an IXP peering address or an upstream's /127 link). The traceroute boundary is the AS edge: ICMPv6 Time-Exceeded responses from anything inside this AS are filtered.

ICMPv6 Type 2 (Packet Too Big) acceptance - active test

Type 2 not honored. Forged ICMPv6 PTB (MTU=1280) had no effect: the next 1500-byte Echo Reply still arrived whole (1460 B, no Fragment Header). PMTUD does not work toward this address from us.
method: ICMPv6 Echo + forged PTB, tested 2026-09-22T13:55:10Z

Failure detail - what to grep in your logs
vantageour sourceyour targetmethodresulttested (UTC)
belgrade2a09:ab81::912a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:10Z
berlin2a06:d1c1:10b::cccc2a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:07Z
duseldorf2a06:d1c1:10d::aaaa2a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:10Z
go6lab2a00:8642:42::752a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:59Z
karsolink2a12:d8c0:105a:9001::a1542a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:06Z
odin2607:fae0:a000::422a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:11Z
t22a01:261:313:b814:2a0:98ff:fe5b:13e42a04:c7c0::1icmp6-echonot_honored2026-09-22T13:55:07Z

Attempt log (belgrade):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (berlin):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (duseldorf):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (go6lab):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: timed out
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (karsolink):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (odin):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

Attempt log (t2):

  1. icmp6-echonot_honored (reply shrank 1460→1460 B)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpno_tcp: tcp/80 not open

To match the corresponding ICMPv6 packet on your side (host firewall, AS edge, or transit tap), look for our PTBs around the timestamps above:

sudo tcpdump -i any -n -e 'icmp6 and ip6[40] = 2 and (src host 2607:fae0:a000::42 or src host 2a00:8642:42::75 or src host 2a01:261:313:b814:2a0:98ff:fe5b:13e4 or src host 2a06:d1c1:10b::cccc or src host 2a06:d1c1:10d::aaaa or src host 2a09:ab81::91 or src host 2a12:d8c0:105a:9001::a154)'

If you see our PTBs arriving but the destination's TCP/Echo flow does not shrink, the drop is in the destination kernel (cause 3 below). If you don't see them at all, drop is upstream of you (cause 2). If you only see them from some of our source IPs but not others, the drop is path-asymmetric - at least one transit on the differing route is filtering.

What does "Type 2 not honored" actually mean? - click to expand

What this test does

Using the icmp6-echo method, we send a 1500-byte ICMPv6 Echo Request, then a forged ICMPv6 Type 2 (Packet Too Big) declaring path MTU=1280, and observe whether the next Echo Reply arrives split into IPv6 fragments. RFC 4890 requires hosts and intermediate networks not to filter ICMPv6 Type 2; the destination's TCP/UDP stack must act on a received PTB by lowering its Path MTU cache for that destination, which makes subsequent segments smaller.

What we measured

The TCP segment size your server emitted before our forged Type 2 was 1460 B; after, it was 1460 B. No change. RFC 4890 ("Type 2 messages MUST NOT be filtered") expects subsequent segments to shrink to fit a Path MTU of 1280 B.

Three plausible causes

  1. Your host firewall is dropping ICMPv6 Type 2 inbound. Many default firewall rule sets only allow Echo Request/Reply and Neighbor Discovery, silently dropping all other ICMPv6 types - including Packet Too Big.
  2. An upstream / transit network is dropping ICMPv6 Type 2 before it reaches you. Some transit ASes filter ICMPv6 messages other than Echo at the edge. The forged PTB never arrives, so your stack never has a chance to act on it.
  3. Your kernel is ignoring the PTB. Linux / BSD stacks normally accept ICMPv6 PTB and update the route cache, but a few sysctls (or a hardened kernel) can be configured to ignore PMTU updates - typically as part of an over-aggressive anti-spoofing or uRPF policy.

How to check & fix (Linux examples)

1. Confirm Type 2 is not blocked at the host firewall:

sudo ip6tables -L INPUT -nv | grep -iE 'icmpv6|packet-too-big'
sudo nft list ruleset 2>/dev/null | grep -A1 'icmpv6'

If you see rules dropping ICMPv6 unconditionally, change them to permit at least icmpv6 type packet-too-big (and destination-unreachable, time-exceeded, parameter-problem per RFC 4890).

2. Confirm the kernel accepts incoming PTB:

sudo sysctl net.ipv6.conf.all.accept_redirects net.ipv4.ip_no_pmtu_disc net.ipv6.route.mtu_expires

The defaults (accept_redirects=1, ip_no_pmtu_disc=0) are the right values for honoring PTB.

3. Live trace: while we have an open TCP flow with a small MSS (we run our test from 2607:fae0:a000::42 on odin, 2a00:8642:42::75 on go6lab, 2a12:d8c0:105a:9001::a154 on karsolink, 2a09:ab81::91 on belgrade, 2a01:261:313:b814:2a0:98ff:fe5b:13e4 on t2, 2a06:d1c1:10a::bbbb on amsterdam, 2a06:d1c1:10d::aaaa on duseldorf and 2a06:d1c1:10b::cccc on berlin), watch for our forged Type 2 arriving on your interface:

sudo tcpdump -i any -n -e 'icmp6 and ip6[40] = 2 and (src host 2607:fae0:a000::42 or src host 2a00:8642:42::75 or src host 2a12:d8c0:105a:9001::a154 or src host 2a09:ab81::91 or src host 2a01:261:313:b814:2a0:98ff:fe5b:13e4 or src host 2a06:d1c1:10a::bbbb or src host 2a06:d1c1:10d::aaaa or src host 2a06:d1c1:10b::cccc)'

If you see our PTBs arriving but TCP segments still stay big, the drop is in your kernel or NIC offload (cause 3). If you don't see them at all, the drop is upstream of you (cause 2) - ask your upstream(s) to permit ICMPv6 Type 2.

4. If your test target above (2026-09-22T13:55:10Z) is a host that you don't own (e.g. a third-party DNS / TLS server you happen to operate prefixes for), the verdict reflects that specific host's behaviour - try the test against a server you do own and we'll happily re-run.

RFC 4890 references: §4.3.1 (Packet Too Big - MUST NOT be dropped), and RFC 8201 for the broader PMTUD requirement.

Multi-vantage path map

Every hop of all vantages’ traceroutes toward the target, drawn left→right, grouped into per-AS bubbles (a hop seen from several vantages is one shared bubble, so converging paths merge). It answers two questions per vantage — shown on each source bubble as echo ✓/⚠/✗ · trace ✓/✗: did the destination reply to ICMPv6 Echo (✓ honored, ⚠ replied but PTB not honored, ✗ no reply), and did the traceroute reach it. A line to the target is drawn only when that vantage got an echo reply — solid if the PTB was honored, dashed if not (reachable but a broken-PMTUD / RFC 4890 violation). The path depth still shows how far the traceroute itself got, and runs of unanswered (* *) hops collapse into one dashed “silent” bubble. Open full size ↗

multi-vantage path diagram for AS31382

From SRB host (SOX, Belgrade)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 12.0ms
4/4
Echo 1500B (DF) 11.9ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
12a09:ab81::10.3ms0%*AS60733PERKE-NET - ZORAN PEROVIC trading as Agencija Perke.NET, RS
2sox-pn.sox.rs
2001:7f8:1e:8::3a
0.4ms0%AS13004SOX - Serbian Open Exchange DOO, RS
32001:7f8:1e:8::3d0.5ms0%AS13004SOX - Serbian Open Exchange DOO, RS
42a02:2d8:0:a00e:232a12.6ms0%-
5GW-AS47147.retn.net
2a02:2d8:0:a00d:232a::1
12.7ms0%AS9002RETN-AS - RETN Limited, GB
62a00:11c0:47:1:47::25213.2ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
72a00:11c0:47:3::6d13.4ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT

tracepath -6

 1?: [LOCALHOST]                        0.016ms pmtu 1500
 1:  _gateway                                              0.970ms 
 1:  _gateway                                              1.038ms 
 2:  sox-pn.sox.rs                                         0.989ms 
 3:  2001:7f8:1e:8::3d                                     0.937ms asymm  2 
 4:  ae8-930.RT.IRX.VIE.AT.retn.net                       11.682ms asymm  3 
 5:  GW-AS47147.retn.net                                  13.088ms asymm  3 
 6:  2a00:11c0:47:1:47::135                               11.964ms asymm  4 
 7:  2a00:11c0:47:3::6d                                   12.366ms asymm  5 
 8:  2a04:c7c0::1                                         14.593ms reached
     Resume: pmtu 1500 hops 8 back 8 

From DE host (Berlin)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 22.2ms
4/4
Echo 1500B (DF) 22.3ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1xe-0-0-13-178.gw01.ber01.as59645.net
2a06:d1c1:100:b::1
0.2ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
2ae0-2453.cr10.ber01.lwlcom.net
2a06:d1c0::dead:beef:1c02
0.5ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
3retn.bcix.de
2001:7f8:19:1::232a:1
10.3ms0%-NA
4RT.ESH.FKT.DE.retn.net
2a02:2d8::57f5:e0b7
10.9ms0%AS9002RETN-AS - RETN Limited, GB
5GW-AS47147.retn.net
2a02:2d8:3:e001:232a::1
30.9ms0%AS9002RETN-AS - RETN Limited, GB
62a00:11c0:47:1:47::14611.6ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
72a00:11c0:47:1:47::15127.6ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
82a00:11c0:47:3::6d28.1ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
92a04:c7c0::123.2ms0%AS31382CANCOM-Austria-IT - CANCOM Austria AG, AT

tracepath -6

 1?: [LOCALHOST]                        0.025ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.787ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.631ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        1.155ms 
 3:  retn.bcix.de                                         11.015ms asymm  5 
 4:  RT.ESH.FKT.DE.retn.net                               11.302ms asymm  5 
 5:  GW-AS47147.retn.net                                  27.304ms asymm  4 
 6:  2a00:11c0:47:1:47::146                               11.582ms asymm  5 
 7:  2a00:11c0:47:1:47::151                               36.955ms asymm 10 
 8:  2a00:11c0:47:3::6d                                   29.052ms asymm 11 
 9:  2a04:c7c0::1                                         23.362ms reached
     Resume: pmtu 1500 hops 9 back 14 

From DE host (Düsseldorf)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 15.5ms
4/4
Echo 1500B (DF) 15.6ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1xe-0-0-12-142.gw01.dus01.as59645.net
2a06:d1c1:100:d::1
0.1ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
2eth1-0-12-h5594.edge5-dus1.bb.wiit.network
2001:4ba0:92f4:3::1
2.4ms0%AS24961MYLOC-AS - WIIT AG, DE
3lag13.agr3-dus3.bb.wiit.network
2001:4ba0:ffe9:7d::1
115.1ms0%AS24961MYLOC-AS - WIIT AG, DE
4lag11.core3-dus1.bb.wiit.network
2001:4ba0:ffe9:115::3
0.3ms0%AS24961MYLOC-AS - WIIT AG, DE
5lag8.core1-dus-ix.bb.wiit.network
2001:4ba0:ffe9:8::2
0.4ms0%AS24961MYLOC-AS - WIIT AG, DE
6de-cix.r60.inx.fra.de.nextlayer.net
2001:7f8::6e4:0:1
3.9ms0%-NA
7ip6-ae10-0-r01.eur.vie.nextlayer.net
2a01:190:1764:ac::2
17.6ms0%AS1764NEXTLAYER-AS - Next Layer Telekommunikationsdienstleistungs- und Beratungs GmbH, AT
82a00:11c0:47:1:47::1464.6ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT

tracepath -6

 1?: [LOCALHOST]                        0.017ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.466ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.951ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.714ms 
 3:  no reply
 4:  lag11.core3-dus1.bb.wiit.network                      0.463ms 
 5:  lag2.core1-dus-ix.bb.wiit.network                     0.455ms 
 6:  ae3-1337.bbr02.anx25.fra.de.anexia-it.net             4.064ms 
 7:  2a00:11c0:47:1:47::143                               10.343ms 
 8:  2a04:c7c0::1                                         16.124ms reached
     Resume: pmtu 1500 hops 8 back 13 

From NL host (go6lab)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 27.9ms
4/4
Echo 1500B (DF) 28.8ms
yes
Type 1 dest-unreach
-
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
12a00:8642:42::22.2ms0%AS203993GNA-DC1-AS - S.J.M. Steffann, NL
2gw.friends.steffann.nl
2a00:8642:1000:f000::1
3.3ms0%*AS203993GNA-DC1-AS - S.J.M. Steffann, NL
3ccr2-ccr1.dc1.nogalliance.org
2a00:8642:dc1:2::b
6.2ms10%AS203993GNA-DC1-AS - S.J.M. Steffann, NL
4ae3-1337.bbr02.anx63.ams.nl.anexia-it.net
2001:7f8:1::a504:7147:1
7.4ms0%-NA
52a00:11c0:47:1:47::21329.7ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
62a00:11c0:47:1:47::13629.3ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
72a00:11c0:47:1:47::13032.0ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
82a04:c7c0::133.6ms0%AS31382CANCOM-Austria-IT - CANCOM Austria AG, AT

Rate-limited ICMPv6: hop 3 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.033ms pmtu 1500
 1:  2a00:8642:42::2                                       2.159ms 
 1:  2a00:8642:42::2                                       5.740ms 
 2:  no reply
 3:  ccr2-ccr1.dc1.nogalliance.org                         5.606ms asymm  2 
 4:  ae3-1337.bbr02.anx63.ams.nl.anexia-it.net             8.484ms asymm  5 
 5:  2a00:11c0:47:1:47::213                               31.055ms asymm 10 
 6:  2a00:11c0:47:1:47::136                               30.220ms asymm 11 
 7:  2a00:11c0:47:1:47::130                               32.090ms asymm 11 
 8:  2a04:c7c0::1                                         32.334ms reached
     Resume: pmtu 1500 hops 8 back 12 

From ITA host (Karsolink)   echo onlyRFC 4890 ✗

filter likely at: destination AS31382 (CANCOM-Austria-IT) · min PMTU on path: 1500

4/4
Echo small (56B) 43.0ms
0/4
Echo 1500B (DF) -
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1*-0%*-
2*---
3*---
4*---
5be47.core1.mil2.he.net
2001:470:e:69::2
12.1ms0%AS6939HURRICANE - Hurricane Electric LLC, US
6be1.core1.zrh2.he.net
2001:470:e:dd::2
15.4ms0%AS6939HURRICANE - Hurricane Electric LLC, US
7*---
8be1.core3.zrh3.he.net
2001:470:0:7e0::2
15.5ms0%AS6939HURRICANE - Hurricane Electric LLC, US
9*---
10ip6-ae10-0-r01.eur.vie.nextlayer.net
2a01:190:1764:ac::2
20.8ms0%AS1764NEXTLAYER-AS - Next Layer Telekommunikationsdienstleistungs- und Beratungs GmbH, AT
112a04:c7c0::118.6ms0%AS31382CANCOM-Austria-IT - CANCOM Austria AG, AT

tracepath -6

 1?: [LOCALHOST]                        0.030ms pmtu 1500
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.685ms 
 3:  no reply
 4:  no reply
 5:  be47.core1.mil2.he.net                               11.592ms 
 6:  be1.core1.zrh2.he.net                                14.137ms 
 7:  no reply
 8:  be1.core3.zrh3.he.net                                14.502ms 
 9:  no reply
10:  no reply
11:  2a04:c7c0::1                                         18.947ms reached
     Resume: pmtu 1500 hops 11 back 12 

From SLO host (6connect)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 16.6ms
4/4
Echo 1500B (DF) 16.6ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1fw1-lju.6connect.com
2607:fae0:a000::2
0.2ms0%*AS80386CONNECT - 6connect, Inc., US
2*---
3*-40%-
42a00:ee0:1:10::20.9ms0%AS5603SIOL-NET - Telekom Slovenije, d.d., SI
5*---
62a00:11c0:47:1:47::14616.3ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
72a00:11c0:47:1:47::15125.9ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
82a00:11c0:47:3::6d26.0ms0%AS47147AS-ANX - Anexia Cloud Solutions GmbH, AT
92a04:c7c0::117.4ms0%AS31382CANCOM-Austria-IT - CANCOM Austria AG, AT

Rate-limited ICMPv6: hop 3 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.024ms pmtu 9000
 1:  fw1-lju.6connect.com                                  1.633ms 
 1:  fw1-lju.6connect.com                                  0.542ms 
 2:  no reply
 3:  no reply
 4:  2a00:ee0:1:10::2                                      1.571ms asymm  3 
 5:  2a00:ee0:1:10::2                                      3.086ms pmtu 1500
 5:  no reply
 6:  2a00:11c0:47:1:47::146                               15.575ms asymm 12 
 7:  2a00:11c0:47:1:47::151                               27.344ms asymm 12 
 8:  2a00:11c0:47:3::6d                                   26.312ms asymm 14 
 9:  2a04:c7c0::1                                         17.877ms reached
     Resume: pmtu 1500 hops 9 back 11 

From SLO host (T-2)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1500

4/4
Echo small (56B) 9.5ms
4/4
Echo 1500B (DF) 9.9ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1*---
22a01:260:1::2253.9ms0%*AS34779T-2-AS - T-2, d.o.o., SI
32a01-260-1-1--9a.core6.t-2.net
2a01:260:1:1::9a
3.3ms0%*AS34779T-2-AS - T-2, d.o.o., SI
42a01-260-1-1--38.core6.t-2.net
2a01:260:1:1::38
3.5ms0%*AS34779T-2-AS - T-2, d.o.o., SI
5*---
6vix-ip6-et-0-1-2-0-r60.inx.vie.at.nextlayer.net @VIX / AAIX / SAIX / TIROL-IX / ERA-IX
2001:7f8:30:0:2:1:0:1764
9.5ms40%-NA
7vix-ip6-et-0-1-2-0-r60.esh.vie.at.nextlayer.net @VIX / AAIX / SAIX / TIROL-IX / ERA-IX
2001:7f8:30:0:1:1:0:1764
9.1ms0%-NA
82a04:c7c0::111.1ms0%AS31382CANCOM-Austria-IT - CANCOM Austria AG, AT

Rate-limited ICMPv6: hop 6 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.030ms pmtu 1500
 1:  no reply
 2:  2a01:260:1::225                                       3.055ms 
 3:  2a01-260-1-1--9a.core6.t-2.net                        2.699ms 
 4:  2a01-260-1-1--38.core6.t-2.net                        2.396ms asymm  3 
 5:  100ge0-0-0-31.core1.vie1.he.net                      10.861ms 
 6:  vix-ip6-et-0-1-2-0-r60.inx.vie.at.nextlayer.net      10.711ms asymm  5 
 7:  no reply
 8:  2a04:c7c0::1                                         11.766ms reached
     Resume: pmtu 1500 hops 8 back 10