AS212891 - ASEVONET EVONET SRLRFC 4890 ✓RPKI ✓ 1/1ASPA -

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AS overview

Test target: 2001:3c40::1 · static prefix probe · address space: unknown · prefixes announced: 1

prefix(es): 2001:3c40::/29

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
2001:3c40::1prbopenrefusedopenrefusedopenrefused??openrefusedopenrefusedopenrefused

RPKI & ASPA

1 of 1 prefix(es) covered by a valid ROA.

PrefixRPKI stateReasonCovering VRP(s)
2001:3c40::/29✓ validmatched VRP (correct origin, length within maxLength)AS212891 /29 maxLen 32 (ripe)

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

We probed 35 arbitrary IPv6 address(es) inside AS212891's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a01:9a80:0:26::a at hop 9 - that router does not answer ICMPv6 Echo. This is not in AS212891'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

Vantage points disagree about Type 2 acceptance - transit ASes on one path may be filtering Type 2 even though the destination's stack accepts it on another path:

Why they disagree - path-asymmetric Type 2 filtering: Both vantages used the ICMPv6 Echo + forged-PTB method on the same destination IP, but reached different verdicts. The destination's stack is the same in both cases - so the difference is in the path: a transit AS on one route filters our forged Type 2 (or its return ICMPv6 carrying the embedded packet) while the other route delivers it intact. The vantage that says honored shows what the destination's stack actually does; the one that says not honored shows that the path between us and them drops Type 2.

Failure detail - what to grep in your logs
vantageour sourceyour targetmethodresulttested (UTC)
belgrade2a09:ab81::912001:3c40::1icmp6-echohonored2026-09-23T11:59:42Z
berlin2a06:d1c1:10b::cccc2001:3c40::1icmp6-echonot_honored2026-09-23T11:59:41Z
duseldorf2a06:d1c1:10d::aaaa2001:3c40::1icmp6-echohonored2026-09-23T11:59:41Z
go6lab2a00:8642:42::752001:3c40::1icmp6-echohonored2026-09-23T12:00:10Z
karsolink2a12:d8c0:105a:9001::a1542001:3c40::1icmp6-echohonored2026-09-23T11:59:42Z
odin2607:fae0:a000::422001:3c40::1icmp6-echonot_honored2026-09-23T11:59:41Z
t22a01:261:313:b814:2a0:98ff:fe5b:13e42001:3c40::1icmp6-echohonored2026-09-23T11:59:41Z

Attempt log (belgrade):

  1. icmp6-echohonored (honored by fragmenting its reply into 2 via the IPv6 Fragment Header, rather than resizing)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpinconclusive: no TCP data from dest in baseline

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. httpinconclusive: no TCP data from dest in baseline

Attempt log (duseldorf):

  1. icmp6-echohonored (honored by fragmenting its reply into 2 via the IPv6 Fragment Header, rather than resizing)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpinconclusive: no TCP data from dest in baseline

Attempt log (go6lab):

  1. icmp6-echohonored (honored by fragmenting its reply into 2 via the IPv6 Fragment Header, rather than resizing)
  2. dns-tcpno_tcp: connect failed: timed out
  3. tlsno_tcp: TLS connect failed
  4. httpinconclusive: no TCP data from dest in baseline

Attempt log (karsolink):

  1. icmp6-echohonored (honored by fragmenting its reply into 2 via the IPv6 Fragment Header, rather than resizing)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpinconclusive: no TCP data from dest in baseline

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. httpinconclusive: no TCP data from dest in baseline

Attempt log (t2):

  1. icmp6-echohonored (honored by fragmenting its reply into 2 via the IPv6 Fragment Header, rather than resizing)
  2. dns-tcpno_tcp: connect failed: [Errno 111] Connection refused
  3. tlsno_tcp: TLS connect failed
  4. httpinconclusive: no TCP data from dest in baseline

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 (2026-09-23T11:59:41Z) 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.

Where the path divergence is

Per-vantage probe + verdict (headline):

Full per-method matrix (all four methods run at each vantage):

vantageicmp6-echodns-tcptlshttp
belgradehonoredno_tcpno_tcpinconclusive
berlinnot_honoredno_tcpno_tcpinconclusive
duseldorfhonoredno_tcpno_tcpinconclusive
go6labhonoredno_tcpno_tcpinconclusive
karsolinkhonoredno_tcpno_tcpinconclusive
odinnot_honoredno_tcpno_tcpinconclusive
t2honoredno_tcpno_tcpinconclusive

These vantage-level disagreements are rooted somewhere in the forward paths. Joining each per-vantage traceroute against the IP→AS lookup from our global yarrp mesh, the first hop where the paths land in different ASes is the most likely site of the offending filter / unreachable AS / Type 2 drop.

Suspect transit ASes (ranked by how often they appear at the divergence point on the path of the worse-classifying vantage): AS212891, AS39120, AS5603.

Diagnosis is path-level, not packet-level: it tells you which transit AS is the prime suspect, not exactly which firewall rule is to blame. Use the tracepath6 output below (when available) for per-hop PMTU evidence on the same path.

Diagnostic interpretation

An operator-targeted diagnostic interpretation can be generated for this AS on demand. The pipeline holds the raw verdicts and the per-hop walk; an AI pass synthesises where to start looking. Click the button below to run it.

tracepath6 per-hop PMTU drilldown

For each target where Type 2 verdicts disagreed across vantages, tracepath -6 ran from every vantage to capture per-hop PMTU evolution along that vantage's actual forward path. A pmtu change entry on a hop means that hop's router generated a PTB and we observed the shrink; absence of any change combined with a not_honored verdict suggests a router somewhere downstream is silently dropping >MTU packets (an RFC 4890 violation) rather than sending a PTB.

Target 2001:3c40::1

amsterdam - verdict ?

(no hops captured)

belgrade - verdict honored

verdict = honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22001:7f8:1e::62
32001:67c:29f0::3:9120:1
42a01:9a80:0:22::2
52a01:9a80:0:26::a
62001:3c40::1
berlin - verdict not_honored

verdict = not_honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22a06:d1c0::dead:beef:1c02
32a00:c380:b200:230::174
42a00:c380:b200:230::23
52001:7f8:8:20:0:e077:0:1
62001:7f8:8:20:0:e077:0:1
7<span class='muted'>no reply</span>
82a01:9a80:0:26::a
92001:3c40::1
duseldorf - verdict honored

verdict = honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22001:4ba0:92f4:3::1
3<span class='muted'>no reply</span>
42001:4ba0:ffe9:109::2
52001:4ba0:ffe9:4f::1
62001:7f8::98d0:0:1
72a01:9a80:0:23::1
82a01:9a80:0:26::a
92001:3c40::1
go6lab - verdict honored

verdict = honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22a00:8642:1000:f000::1
32a00:8642:dc1:2::b
42001:7f8:1::a503:9120:1
52a01:9a80:0:23::1
62a01:9a80:0:26::a
72001:3c40::1
karsolink - verdict honored

verdict = honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22a12:d8c0:109f:121::a1
32a12:d8c0:101f:6::1
42001:7f8:112::12
52a01:9a80:0:22::2
62a01:9a80:0:26::a
72001:3c40::1
odin - verdict not_honored

verdict = not_honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22607:fae0:a000:2::2
32a00:ee1:800:9::1
42a00:ee0:1:10::2
52a00:ee0:1:10::2
62a01:9a80:0:23::1
72a01:9a80:0:26::a
82001:3c40::1
t2 - verdict honored

verdict = honored; final pmtu = 1500

#hop IPpmtu change
1<span class='muted'>no reply</span>
22a01:260:1::225
32a01:260:1:1::9c
42001:7f8:46:0:1:0:5:7463
52001:67c:29f0::3:9120:1
62a01:9a80:0:22::2
72a01:9a80:0:26::a
82001:3c40::1

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 AS212891

From SRB host (SOX, Belgrade)   openRFC 4890 ✓

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

4/4
Echo small (56B) 55.8ms
4/4
Echo 1500B (DF) 55.9ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
12a09:ab81::10.2ms0%*AS60733PERKE-NET - ZORAN PEROVIC trading as Agencija Perke.NET, RS
22001:7f8:1e::628.8ms0%AS13004SOX - Serbian Open Exchange DOO, RS
3as39120.v6.netix.net
2001:67c:29f0::3:9120:1
38.2ms0%-NA
42a01:9a80:0:22::251.0ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
52a01:9a80:0:26::a52.8ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
62001:3c40::152.8ms0%AS212891ASEVONET - EVONET SRL, IT

tracepath -6

 1?: [LOCALHOST]                        0.014ms pmtu 1500
 1:  _gateway                                              0.449ms 
 1:  _gateway                                              0.742ms 
 2:  2001:7f8:1e::62                                       7.982ms 
 3:  as39120.v6.netix.net                                 38.358ms 
 4:  2a01:9a80:0:22::2                                    49.484ms 
 5:  2a01:9a80:0:26::a                                    53.018ms 
 6:  2001:3c40::1                                         55.482ms reached
     Resume: pmtu 1500 hops 6 back 6 

From DE host (Berlin)   openRFC 4890 ✗

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

4/4
Echo small (56B) 54.9ms
4/4
Echo 1500B (DF) 55.0ms
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
0.3ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
2ae0-2453.cr10.ber01.lwlcom.net
2a06:d1c0::dead:beef:1c02
0.8ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
3ae0-150.cr10.fra01.lwlcom.net
2a00:c380:b200:230::174
10.1ms0%AS50629LWLCOM - LWLcom GmbH, DE
4ae0-20.cr10.fra07.lwlcom.net
2a00:c380:b200:230::31
10.2ms0%AS50629LWLCOM - LWLcom GmbH, DE
5ae0-40.cr10.fra04.lwlcom.net
2a00:c380:b200:230::76
10.0ms0%AS50629LWLCOM - LWLcom GmbH, DE
6as57463.frankfurt.megaport.com
2001:7f8:8:20:0:e077:0:1
10.3ms0%-NA
7*---
82a01:9a80:0:22::240.7ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
92a01:9a80:0:26::a40.4ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
102001:3c40::147.0ms0%AS212891ASEVONET - EVONET SRL, IT

tracepath -6

 1?: [LOCALHOST]                        0.020ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.329ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.341ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        0.972ms 
 3:  ae0-150.cr10.fra01.lwlcom.net                        10.379ms asymm  7 
 4:  ae0-20.cr10.fra07.lwlcom.net                         10.427ms asymm  6 
 5:  ae0-40.cr10.fra04.lwlcom.net                         10.535ms 
 6:  as57463.frankfurt.megaport.com                       10.606ms 
 7:  2a01:9a80:0:22::2                                    41.684ms asymm 12 
 8:  2a01:9a80:0:26::a                                    40.679ms asymm 13 
 9:  2001:3c40::1                                         55.325ms 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) 32.0ms
4/4
Echo 1500B (DF) 32.1ms
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
0.2ms0%*AS59645WYBT-NET - Tobias Fiebig, DE
2eth1-0-12-h5594.edge5-dus1.bb.wiit.network
2001:4ba0:92f4:3::1
0.9ms0%AS24961MYLOC-AS - WIIT AG, DE
3*---
4lag30.core3-dus1.bb.wiit.network
2001:4ba0:ffe9:109::2
0.2ms0%AS24961MYLOC-AS - WIIT AG, DE
5lag2.core1-dus-ix.bb.wiit.network
2001:4ba0:ffe9:4f::1
0.4ms0%AS24961MYLOC-AS - WIIT AG, DE
6de-cix.convergenze.it
2001:7f8::98d0:0:1
23.7ms0%-NA
72a01:9a80:0:23::129.8ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
82a01:9a80:0:26::a29.7ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
92001:3c40::133.3ms0%AS212891ASEVONET - EVONET SRL, IT

tracepath -6

 1?: [LOCALHOST]                        0.018ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.332ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.368ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.159ms 
 3:  no reply
 4:  lag30.core3-dus1.bb.wiit.network                      0.410ms 
 5:  lag8.core1-dus-ix.bb.wiit.network                     0.574ms 
 6:  de-cix.convergenze.it                                23.529ms asymm  3 
 7:  2a01:9a80:0:23::1                                    28.988ms asymm 11 
 8:  2a01:9a80:0:26::a                                    28.682ms asymm 12 
 9:  2001:3c40::1                                         35.402ms reached
     Resume: pmtu 1500 hops 9 back 13 

From NL host (go6lab)   openRFC 4890 ✓

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

4/4
Echo small (56B) 45.7ms
4/4
Echo 1500B (DF) 47.7ms
yes
Type 1 dest-unreach
-
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
12a00:8642:42::21.8ms0%AS203993GNA-DC1-AS - S.J.M. Steffann, NL
2*-0%*-
3ccr2-ccr1.dc1.nogalliance.org
2a00:8642:dc1:2::b
1.5ms0%AS203993GNA-DC1-AS - S.J.M. Steffann, NL
42001:7f8:1::a503:9120:139.4ms0%-NA
52a01:9a80:0:23::137.7ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
62a01:9a80:0:26::a39.9ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
72001:3c40::145.4ms0%AS212891ASEVONET - EVONET SRL, IT

tracepath -6

 1?: [LOCALHOST]                        0.042ms pmtu 1500
 1:  2a00:8642:42::2                                       2.331ms 
 1:  2a00:8642:42::2                                       2.782ms 
 2:  gw.friends.steffann.nl                                4.785ms 
 3:  ccr2-ccr1.dc1.nogalliance.org                         4.622ms asymm  2 
 4:  2001:7f8:1::a503:9120:1                              32.380ms asymm  5 
 5:  2a01:9a80:0:23::1                                    42.946ms 
 6:  2a01:9a80:0:26::a                                    43.950ms 
 7:  2001:3c40::1                                         50.804ms reached
     Resume: pmtu 1500 hops 7 back 7 

From ITA host (Karsolink)   openRFC 4890 ✓

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

4/4
Echo small (56B) 31.9ms
3/4
Echo 1500B (DF) 32.2ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
1*-0%*-
2*---
32a12:d8c0:109f:106::a23.1ms80%AS204471KARSOLINK - 2S Computers SRL, IT
4convergenze.minap.it
2001:7f8:c5::a503:9120:1
9.3ms0%AS39120Convergenze S.p.A.
52a01:9a80:0:22::226.3ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
62a01:9a80:0:26::a26.9ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
72001:3c40::131.0ms0%AS212891ASEVONET - EVONET SRL, IT

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

tracepath -6

 1?: [LOCALHOST]                        0.035ms pmtu 1500
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.851ms 
 3:  no reply
 4:  convergenze-v6.mix-it.net                             9.103ms 
 5:  2a01:9a80:0:22::2                                    27.077ms 
 6:  2a01:9a80:0:26::a                                    27.615ms 
 7:  2001:3c40::1                                         31.915ms reached
     Resume: pmtu 1500 hops 7 back 7 

From SLO host (6connect)   echo onlyRFC 4890 ✗

filter likely at: destination AS212891 (ASEVONET) · min PMTU on path: 1500

4/4
Echo small (56B) 36.2ms
0/4
Echo 1500B (DF) -
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
0.5ms0%*AS80386CONNECT - 6connect, Inc., US
2ccr-to-fw-ccr1-gw-lju.6connect.com
2607:fae0:a000:2::2
0.6ms-AS80386CONNECT - 6connect, Inc., US
32a00:ee1:800:9::11.8ms60%AS5603SIOL-NET - Telekom Slovenije, d.d., SI
42a00:ee0:1:15::21.0ms0%AS5603SIOL-NET - Telekom Slovenije, d.d., SI
5de-cix.convergenze.it
2001:7f8::98d0:0:1
31.8ms0%-NA
62a01:9a80:0:23::130.5ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
72a01:9a80:0:26::a31.0ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
82001:3c40::137.4ms0%AS212891ASEVONET - EVONET SRL, IT

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

tracepath -6

 1?: [LOCALHOST]                        0.021ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.691ms 
 1:  fw1-lju.6connect.com                                  0.665ms 
 2:  no reply
 3:  2a00:ee1:800:9::1                                     5.814ms 
 4:  2a00:ee0:1:15::2                                      3.026ms asymm  3 
 5:  2a00:ee0:1:15::2                                      1.580ms pmtu 1500
 5:  de-cix.convergenze.it                                31.505ms asymm 10 
 6:  2a01:9a80:0:23::1                                    31.715ms asymm  9 
 7:  2a01:9a80:0:26::a                                    32.334ms asymm 10 
 8:  2001:3c40::1                                         35.364ms reached
     Resume: pmtu 1500 hops 8 back 11 

From SLO host (T-2)   openRFC 4890 ✓

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

4/4
Echo small (56B) 45.5ms
4/4
Echo 1500B (DF) 45.9ms
yes
Type 1 dest-unreach
443,80
TCP responds on

Path (traceroute + mtr + PTR)

#IP / PTRRTTmtr lossASAS holder
12a01:261:313:b814::10.5ms0%*AS34779T-2-AS - T-2, d.o.o., SI
22a01:260:1::2252.2ms0%*AS34779T-2-AS - T-2, d.o.o., SI
32a01-260-1-1--9c.core6.t-2.net
2a01:260:1:1::9c
2.1ms0%*AS34779T-2-AS - T-2, d.o.o., SI
42001:7f8:46:0:1:0:5:746316.1ms0%AS51988ARNES-SIX - ARNES, SI
5as39120.v6.netix.net
2001:67c:29f0::3:9120:1
24.0ms0%-NA
62a01:9a80:0:22::238.7ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
72a01:9a80:0:26::a38.3ms0%AS39120CONVERGENZE-AS - Convergenze S.p.A., IT
82001:3c40::144.4ms0%AS212891ASEVONET - EVONET SRL, IT

tracepath -6

 1?: [LOCALHOST]                        0.028ms pmtu 1500
 1:  no reply
 2:  2a01:260:1::225                                       3.635ms 
 3:  2a01-260-1-1--9c.core6.t-2.net                        3.178ms 
 4:  2001:7f8:46:0:1:0:5:7463                             15.111ms 
 5:  ???                                                  23.981ms 
 6:  2a01:9a80:0:22::2                                    40.170ms 
 7:  2a01:9a80:0:26::a                                    39.941ms 
 8:  2001:3c40::1                                         43.187ms reached
     Resume: pmtu 1500 hops 8 back 8