IPv6 prefix announced, but nothing inside is responding yet. AS60236 announces 1 IPv6 prefix(es) to the global routing table - that’s the part that BGP and our route-server scrape confirm. But our active discovery (curated hostnames, holder-derived domains, authoritative DNS NS/SOA/MX, certificate-transparency hostnames, RIPE Atlas, RDAP, IPv6 Hitlist) found no ICMPv6-responsive host inside the prefix on either vantage, and a yarrp pass against random addresses inside the prefix produced zero in-prefix hops (no router on the path through the AS replied with Time-Exceeded for any random target). That combination usually means the announcement is configured but the addresses inside aren’t in active use yet. The BGP route is there; the operational deployment is still ahead.
AS overview
Test target: 2a0f:2a00::1 · (no live host found) · address space: PA · prefixes announced: 1
prefix(es): 2a0f:2a00::/48
RPKI & ASPA
1 of 1 prefix(es) covered by a valid ROA.
| Prefix | RPKI state | Reason | Covering VRP(s) |
|---|---|---|---|
2a0f:2a00::/48 | ✓ valid | matched VRP (correct origin, length within maxLength) | AS60236 /48 maxLen 48 (ripe) |
Random-IP probe (yarrp) into the AS' prefixes
We probed 15 arbitrary IPv6 address(es) inside AS60236's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2001:19f0:5000:344::33 at hop 15 - that router answers ICMPv6 Echo. This is not in AS60236'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 active test inconclusive: no Echo Reply to 1300-byte probe.
method: ICMPv6 Echo + forged PTB, tested 2026-05-25T12:37:11Z
Failure detail — what to grep in your logs
| vantage | our source | your target | method | result | tested (UTC) |
|---|---|---|---|---|---|
| go6lab | 2a00:8642:42::75 | 2a0f:2a00::1 | icmp6-echo | no_echo | 2026-05-25T12:37:11Z |
| karsolink | 2a12:d8c0:105a:9001::a154 | 2a0f:2a00::1 | icmp6-echo | no_echo | 2026-05-25T12:48:21Z |
| odin | 2607:fae0:a000::42 | 2a0f:2a00::1 | icmp6-echo | no_echo | 2026-05-25T12:36:43Z |
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) transit only unreachable
filter likely at: past AS20473 (AS-VULTR) · 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 | 1.7ms | 0% | AS203993 | STEFFANN-DC-AS - S.J.M. Steffann, NL |
| 2 | * | - | 0%* | - | |
| 3 | 2a00:1ca8:1::194 | 4.6ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 4 | 2a03:3f40::10:33 | 4.6ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 5 | 2001:7f8:1::a502:473:1 | 6.0ms | 0% | - | NA |
| 6 | ethernetae1-sr1.ams1.constant.com 2001:19f0:fc00::a48:406 | 17.6ms | 0% | - | NA |
| 7 | ethernetswp55-ds1-u2-r060714-a.ams1.constant.com 2001:19f0:fc00::a48:1f2 | 5.4ms | 0% | - | NA |
| 8 | 2001:19f0:5000:344::33 | 5.5ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 9 | * | - | - | - | |
| 10 | * | - | - | - | |
| 11 | * | - | - | - | |
| 12 | * | - | - | - | |
| 13 | * | - | - | - | |
| 14 | * | - | - | - | |
| 15 | * | - | - | - | |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
tracepath -6
1?: [LOCALHOST] 0.035ms pmtu 1500
1: 2a00:8642:42::3 1.391ms
1: 2a00:8642:42::3 1.537ms
2: no reply
3: 2a00:1ca8:1::194 3.725ms
4: 2a03:3f40::10:33 5.329ms
5: 2001:7f8:1::a502:473:1 7.957ms asymm 6
6: ethernetae1-sr2.ams1.constant.com 7.102ms asymm 7
7: ethernetswp56-ds1-u2-r060714-a.ams1.constant.com 5.959ms asymm 8
8: 2001:19f0:5000:344::33 6.144ms
9: no reply
10: no reply
11: no reply
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 ITA host (Karsolink) transit only unreachable
filter likely at: past AS20473 (AS-VULTR) · 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 | * | - | 0%* | - | |
| 2 | 2a12:d8c0:109f:121::a1 | 0.4ms | 0%* | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 3 | 2a12:d8c0:101f:6::1 | 10.1ms | 20% | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 4 | 2a03:b020:1:51::a | 10.1ms | 0% | AS41327 | FIBERTELECOM-AS - Fiber Telecom S.p.A., IT |
| 5 | 2a03:b020::222 | 26.0ms | 0% | AS41327 | FIBERTELECOM-AS - Fiber Telecom S.p.A., IT |
| 6 | 2001:7f8:12a::204 | 27.6ms | 0% | - | NA |
| 7 | * | - | - | - | |
| 8 | * | - | - | - | |
| 9 | 2001:19f0:5000:344::33 | 27.3ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 10 | * | - | - | - | |
| 11 | * | - | - | - | |
| 12 | * | - | - | - | |
| 13 | * | - | - | - | |
| 14 | * | - | - | - | |
| 15 | * | - | - | - | |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
Rate-limited ICMPv6: hop 3 (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: no reply
3: 2a12:d8c0:101f:6::1 10.623ms
4: 2a03:b020:1:51::a 11.074ms
5: 2a03:b020::222 26.663ms
6: 2001:7f8:12a::204 28.183ms asymm 7
7: no reply
8: no reply
9: 2001:19f0:5000:344::33 27.764ms
10: no reply
11: no reply
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) transit only unreachable
filter likely at: past AS20473 (AS-VULTR) · 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 | 0.3ms | 0%* | AS8038 | 6CONNECT - 6connect, Inc., US |
| 2 | * | - | - | - | |
| 3 | 2a00:ee1:800:9::1 | 2.1ms | 0% | AS5603 | SIOL-NET - Telekom Slovenije, d.d., SI |
| 4 | 2a00:ee0:1:10::2 | 1.1ms | 0% | AS5603 | SIOL-NET - Telekom Slovenije, d.d., SI |
| 5 | 2a11:4142:2002 | 1.1ms | 0% | - | |
| 6 | r2-vie1-at.as5405.net 2a11:4140::1e | 23.9ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 7 | r2-vie2-at.as5405.net 2a11:4140::20 | 24.4ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 8 | r4-fra3-de.as5405.net 2a11:4140::37 | 25.6ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 9 | r6-ams1-nl.as5405.net 2a11:4140::54 | 23.4ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 10 | r7-ams1-nl.as5405.net 2a11:4140::55 | 23.4ms | 0% | AS5405 | INTERDOTLINK - Inter.link GmbH, DE |
| 11 | 2001:4de0:0:bbbb::b | 23.8ms | 0% | AS34343 | BIP-AS - Eweka Internet Services B.V., NL |
| 12 | 2001:7f8:1::a502:473:1 | 24.1ms | 0% | - | NA |
| 13 | ethernetae1-sr2.ams1.constant.com 2001:19f0:fc00::a48:40a | 25.4ms | 0% | - | NA |
| 14 | ethernetet-0-0-49-ds1-j2-r060714-b.ams1.constant.com 2001:19f0:fc00::a48:17e | 28.3ms | 0% | - | NA |
| 15 | 2001:19f0:5000:344::33 | 24.1ms | 0% | AS20473 | AS-VULTR - The Constant Company, LLC, US |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
tracepath -6
1?: [LOCALHOST] 0.025ms pmtu 1500
1: fw1-lju.6connect.com 0.472ms
1: fw1-lju.6connect.com 0.486ms
2: no reply
3: 2a00:ee1:800:9::1 2.200ms
4: 2a00:ee0:1:15::2 1.255ms asymm 3
5: 2a11:4142:2002:: 0.916ms asymm 6
6: r2-vie1-at.as5405.net 23.573ms asymm 16
7: r2-vie2-at.as5405.net 23.640ms asymm 16
8: r4-fra3-de.as5405.net 23.482ms asymm 14
9: r6-ams1-nl.as5405.net 23.427ms asymm 14
10: r7-ams1-nl.as5405.net 23.614ms asymm 13
11: 2001:4de0:0:bbbb::b 23.660ms
12: 2001:7f8:1::a502:473:1 24.369ms
13: ethernetae1-sr2.ams1.constant.com 24.979ms
14: ethernetet-0-0-49-ds1-j2-r060714-b.ams1.constant.com 26.445ms asymm 13
15: 2001:19f0:5000:344::33 24.295ms asymm 16
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