AS overview
Test target: 2a11:fe80:fab3::ffff · static prefix probe · address space: PA · prefixes announced: 2
prefix(es): 2a11:fe80::/32, 2a11:fe80:fab3::/48
Targets & per-vantage-point probe results (1 target(s) across 3 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 / hostname | Source | NL host (go6lab) | ITA host (Karsolink) | SLO host (6connect) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ping | 1500B | :80 | :443 | reached | ping | 1500B | :80 | :443 | reached | ping | 1500B | :80 | :443 | reached | ||
2a11:fe80:fab3::ffff | prb | ✗ | ✗ | ? | ? | - | ✗ | ✗ | ? | ? | - | ✗ | ✗ | ? | ? | - |
RPKI & ASPA
2 of 2 prefix(es) covered by a valid ROA.
| Prefix | RPKI state | Reason | Covering VRP(s) |
|---|---|---|---|
2a11:fe80::/32 | ✓ valid | matched VRP (correct origin, length within maxLength) | AS209209 /32 maxLen 48 (ripe) |
2a11:fe80:fab3::/48 | ✓ valid | matched VRP (correct origin, length within maxLength) | AS209209 /48 maxLen 48 (ripe); AS209209 /32 maxLen 48 (ripe) |
Random-IP probe (yarrp) into the AS' prefixes
At least one router inside AS209209's announced prefix replied during the random-target probe. Hop(s): 2a11:fe80:46::. These are candidate targets for direct testing.
ICMPv6 Type 2 (Packet Too Big) acceptance - active test
Type 2 active test inconclusive: no Echo Reply to 1300-byte probe.
method: ICMPv6 Echo + forged PTB, tested 2026-05-30T12:48:32Z
Failure detail — what to grep in your logs
| vantage | our source | your target | method | result | tested (UTC) |
|---|---|---|---|---|---|
| go6lab | 2a00:8642:42::75 | 2a11:fe80:fab3::ffff | icmp6-echo | no_echo | 2026-05-30T12:48:32Z |
| karsolink | 2a12:d8c0:105a:9001::a154 | 2a11:fe80:fab3::ffff | icmp6-echo | no_echo | 2026-05-30T12:59:05Z |
| odin | 2607:fae0:a000::42 | 2a11:fe80:fab3::ffff | icmp6-echo | no_echo | 2026-05-30T12:48:12Z |
Attempt log (go6lab):
icmp6-echo→ no_echo: no Echo Reply to 1300-byte probedns-tcp→ no_tcp: connect failed: timed outtls→ no_tcp: TLS connect failedhttp→ no_tcp: tcp/80 not open
Attempt log (karsolink):
icmp6-echo→ no_echo: no Echo Reply to 1300-byte probedns-tcp→ no_tcp: connect failed: timed outtls→ no_tcp: TLS connect failedhttp→ no_tcp: tcp/80 not open
Attempt log (odin):
icmp6-echo→ no_echo: no Echo Reply to 1300-byte probedns-tcp→ no_tcp: connect failed: timed outtls→ no_tcp: TLS connect failedhttp→ no_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 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 one of our two source IPs, the drop is path-asymmetric — one transit on the asymmetric route is filtering, the other is not.
From NL host (go6lab) all blocked
filter likely at: before path completes · min PMTU on path: 1500
0/4
Echo small (56B) -
0/4
Echo 1500B (DF) -
no
Type 1 dest-unreach
-
TCP responds on
Path (traceroute + mtr + PTR)
| # | IP / PTR | RTT | mtr loss | AS | AS holder |
|---|---|---|---|---|---|
| 1 | 2a00:8642:42::3 | 1.2ms | 0% | AS203993 | STEFFANN-DC-AS - S.J.M. Steffann, NL |
| 2 | gw.friends.steffann.nl 2a00:8642:1000:f000::1 | 2.0ms | 0%* | AS203993 | STEFFANN-DC-AS - S.J.M. Steffann, NL |
| 3 | 2a00:1ca8:1::194 | 2.0ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 4 | 2a03:3f40::10:33 | 4.5ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 5 | ae22-404.ams10.core-backbone.com 2a01:4a0:1338:155::1 | 6.0ms | 0% | AS201011 | CORE-BACKBONE - Core-Backbone GmbH, DE |
| 6 | ae6-2082.ham10.core-backbone.com 2a01:4a0:0:2082::25 | 10.4ms | 0% | AS201011 | CORE-BACKBONE - Core-Backbone GmbH, DE |
| 7 | ae1-2085.cop10.core-backbone.com 2a01:4a0:0:2085::38 | 17.0ms | 0% | AS201011 | CORE-BACKBONE - Core-Backbone GmbH, DE |
| 8 | ae11-2086.sth10.core-backbone.com 2a01:4a0:0:2086::34 | 26.0ms | 0% | AS201011 | CORE-BACKBONE - Core-Backbone GmbH, DE |
| 9 | netnod-ix-ge-g-sth-1500.constant.com 2001:7f8:d:fe::86 | 35.6ms | 0% | - | NA |
| 10 | ethernetswp55-ds1-u2-r102-a.sto1.constant.com 2001:19f0:fc00::a55:46 | 26.9ms | 0% | - | NA |
| 11 | 2a05:f480:2000:425::33 | 26.6ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 12 | 2a11:fe80:46 | 26.7ms | 0% | - | |
| 13 | 2a11:fe80:46 | 26.9ms | 0% | - | |
| 14 | * | - | - | - | |
| 15 | * | - | - | - | |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
tracepath -6
1?: [LOCALHOST] 0.059ms pmtu 1500
1: 2a00:8642:42::3 1.410ms
1: 2a00:8642:42::3 1.538ms
2: gw.friends.steffann.nl 2.529ms
3: 2a00:1ca8:1::194 3.073ms
4: 2a03:3f40::10:33 5.423ms
5: ae22-404.ams10.core-backbone.com 5.608ms
6: ae3-2088.cop10.core-backbone.com 17.752ms
7: ae1-2085.cop10.core-backbone.com 17.467ms
8: ae11-2086.sth10.core-backbone.com 27.167ms
9: netnod-ix-ge-g-sth-1500.constant.com 28.502ms
10: ethernetae7-sr1.sto1.constant.com 30.475ms
11: 2a05:f480:2000:425::33 26.860ms asymm 13
12: 2a11:fe80:46:: 27.748ms asymm 14
13: 2a11:fe80:46:: 27.326ms asymm 14
14: no reply
15: no reply
16: no reply
17: no reply
18: no reply
19: no reply
20: no reply
21: no reply
22: no reply
23: no reply
24: no reply
Too many hops: pmtu 1500
Resume: pmtu 1500 From ITA host (Karsolink) all blocked
filter likely at: before path completes · min PMTU on path: 1500
0/4
Echo small (56B) -
0/4
Echo 1500B (DF) -
no
Type 1 dest-unreach
-
TCP responds on
Path (traceroute + mtr + PTR)
| # | IP / PTR | RTT | mtr loss | AS | AS holder |
|---|---|---|---|---|---|
| 1 | karsolink-01.net.karsolink.com 2a12:d8c0:105a:9001::1 | 0.2ms | 0%* | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 2 | 2a12:d8c0:109f:121::a1 | 0.4ms | 0%* | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 3 | 2a12:d8c0:101f:6::1 | 10.1ms | 10% | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 4 | 2a03:b020:1:51::a | 10.1ms | 10% | AS41327 | FIBERTELECOM-AS - Fiber Telecom S.p.A., IT |
| 5 | ae16-100.cr0-mil2.ip6.gtt.net 2001:668:0:3:ffff:0:d5fe:dc4d | 10.2ms | 10% | AS3257 | GTT-BACKBONE - GTT Communications Inc., US |
| 6 | 2001:668:0:2:ffff:0:8d88:6caa | 41.4ms | 10% | AS3257 | GTT-BACKBONE - GTT Communications Inc., US |
| 7 | 2001:668:0:3:ffff:1:0:18ca | 57.3ms | 0% | AS3257 | GTT-BACKBONE - GTT Communications Inc., US |
| 8 | * | - | - | - | |
| 9 | * | - | - | - | |
| 10 | 2a05:f480:2000:425::33 | 57.4ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 11 | 2a11:fe80:46 | 57.6ms | 0% | - | |
| 12 | * | - | - | - | |
| 13 | * | - | - | - | |
| 14 | * | - | - | - | |
| 15 | * | - | - | - | |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
Rate-limited ICMPv6: hop 3, hop 4, hop 5, hop 6 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).
tracepath -6
1?: [LOCALHOST] 0.035ms pmtu 1500
1: karsolink-01.net.karsolink.com 0.808ms
1: karsolink-01.net.karsolink.com 0.713ms
2: no reply
3: 2a12:d8c0:101f:6::1 10.458ms
4: 2a03:b020:1:51::a 10.542ms
5: ae16-100.cr0-mil2.ip6.gtt.net 12.492ms
6: 2001:668:0:2:ffff:0:8d88:6caa 41.935ms asymm 7
7: 2001:668:0:3:ffff:1:0:18ca 58.056ms
8: no reply
9: no reply
10: 2a05:f480:2000:425::33 58.276ms asymm 11
11: 2a11:fe80:46:: 58.334ms asymm 12
12: no reply
13: no reply
14: no reply
15: no reply
16: no reply
17: no reply
18: no reply
19: no reply
20: no reply
21: no reply
22: no reply
23: no reply
24: no reply
Too many hops: pmtu 1500
Resume: pmtu 1500 From SLO host (6connect) all blocked
filter likely at: before path completes · min PMTU on path: 1500
0/4
Echo small (56B) -
0/4
Echo 1500B (DF) -
no
Type 1 dest-unreach
-
TCP responds on
Path (traceroute + mtr + PTR)
| # | IP / PTR | RTT | mtr loss | AS | AS holder |
|---|---|---|---|---|---|
| 1 | fw1-lju.6connect.com 2607:fae0:a000::2 | 0.2ms | 0%* | AS8038 | 6CONNECT - 6connect, Inc., US |
| 2 | ccr-to-fw-ccr1-gw-lju.6connect.com 2607:fae0:a000:2::2 | 0.4ms | 0%* | AS8038 | 6CONNECT - 6connect, Inc., US |
| 3 | 2a00:ee1:800:9::1 | 1.9ms | 0% | AS5603 | SIOL-NET - Telekom Slovenije, d.d., SI |
| 4 | 2a00:ee0:1:10::2 | 0.9ms | 0% | AS5603 | SIOL-NET - Telekom Slovenije, d.d., SI |
| 5 | 2a11:4142:2002 | 0.8ms | 0% | - | |
| 6 | r2-vie1-at.as5405.net 2a11:4140::1e | 29.0ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 7 | r1-vie1-at.as5405.net 2a11:4140::1d | 29.1ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 8 | r1-prg1-cz.as5405.net 2a11:4140::21 | 29.1ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 9 | r2-prg1-cz.as5405.net 2a11:4140::22 | 29.0ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 10 | r2-ber2-de.as5405.net 2a11:4140::24 | 29.1ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 11 | r3-ber1-de.as5405.net 2a11:4140::2 | 29.1ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 12 | r4-ber1-de.as5405.net 2a11:4140::3 | 29.4ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 13 | r1-sto2-se.as5405.net 2a11:4140::47 | 29.2ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 14 | netnod-ix-ge-a-sth-1500.inter.link 2001:7f8:d:ff::180 | 29.2ms | 0% | - | NA |
| 15 | netnod-ix-ge-g-sth-1500.constant.com 2001:7f8:d:fe::86 | 39.8ms | 0% | - | NA |
| 16 | ethernetae7-sr1.sto1.constant.com 2001:19f0:fc00::a54:122 | 30.0ms | 0% | - | NA |
| 17 | ethernetswp55-ds1-u2-r102-a.sto1.constant.com 2001:19f0:fc00::a55:46 | 29.4ms | 0% | - | NA |
| 18 | 2a05:f480:2000:425::33 | 29.6ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 19 | 2a11:fe80:46 | 29.7ms | 0% | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
tracepath -6
1?: [LOCALHOST] 0.060ms pmtu 1500
1: fw1-lju.6connect.com 0.669ms
1: fw1-lju.6connect.com 0.519ms
2: no reply
3: 2a00:ee1:800:9::1 2.012ms
4: 2a00:ee0:1:15::2 1.103ms asymm 3
5: 2a11:4142:2002:: 1.167ms asymm 6
6: r2-vie1-at.as5405.net 29.260ms asymm 22
7: r1-vie1-at.as5405.net 29.131ms asymm 21
8: r1-prg1-cz.as5405.net 29.370ms asymm 21
9: r2-prg1-cz.as5405.net 29.429ms asymm 19
10: r2-ber2-de.as5405.net 29.285ms asymm 18
11: r3-ber1-de.as5405.net 29.371ms asymm 18
12: r4-ber1-de.as5405.net 29.292ms asymm 16
13: r1-sto2-se.as5405.net 29.344ms asymm 16
14: netnod-ix-ge-a-sth-1500.inter.link 29.253ms asymm 15
15: netnod-ix-ge-b-sth-1500.constant.com 39.483ms asymm 14
16: ethernetae6-sr2.sto1.constant.com 30.349ms
17: ethernetswp55-ds1-u2-r102-b.sto1.constant.com 29.680ms asymm 18
18: 2a05:f480:2000:425::33 29.759ms
19: 2a11:fe80:46:: 29.858ms
20: no reply
21: no reply
22: no reply
23: no reply
24: no reply
Too many hops: pmtu 1500
Resume: pmtu 1500