AS overview
Test target: 2a02:c680::1 · static prefix probe · address space: PA · prefixes announced: 1
prefix(es): 2a02:c680::/31
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 | ||
2a02:c680::1 | prb | ✗ | ✗ | ? | ? | - | ✗ | ✗ | ? | ? | - | ✗ | ✗ | ? | ? | - |
MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO peering
MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO member - Selective peering, peering member, since 2013-09-06. IPv6 LAN: 2001:7f8:b:100:1d1:a519:6983:135. Locations: -.
RPKI & ASPA
0 of 1 prefix(es) covered by a valid ROA, 1 not-found.
| Prefix | RPKI state | Reason | Covering VRP(s) |
|---|---|---|---|
2a02:c680::/31 | - not-found | no covering VRP |
Random-IP probe (yarrp) into the AS' prefixes
We probed 14 arbitrary IPv6 address(es) inside AS196983's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a12:d8c0:101f:6::1 at hop 18 - that router answers ICMPv6 Echo. This is not in AS196983'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 2026-05-30T12:44:30Z
Failure detail — what to grep in your logs
| vantage | our source | your target | method | result | tested (UTC) |
|---|---|---|---|---|---|
| go6lab | 2a00:8642:42::75 | 2a02:c680::1 | icmp6-echo | no_echo | 2026-05-30T12:44:30Z |
| karsolink | 2a12:d8c0:105a:9001::a154 | 2a02:c680::1 | icmp6-echo | no_echo | 2026-05-30T12:51:19Z |
| odin | 2607:fae0:a000::42 | 2a02:c680::1 | icmp6-echo | no_echo | 2026-05-30T12:44:16Z |
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: [Errno 101] Network is unreachabletls→ 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: [Errno 101] Network is unreachabletls→ 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: past AS174 (COGENT-174) · min PMTU on path: 1500
Path (traceroute + mtr + PTR)
| # | IP / PTR | RTT | mtr loss | AS | AS holder |
|---|---|---|---|---|---|
| 1 | 2a00:8642:42::3 | 1.0ms | 0% | AS203993 | STEFFANN-DC-AS - S.J.M. Steffann, NL |
| 2 | * | - | 0%* | - | |
| 3 | 2a00:1ca8:1::194 | 2.8ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 4 | 2a03:3f40::10:41 | 2.6ms | 0% | AS50673 | Serverius-as - Serverius Holding B.V., NL |
| 5 | * | - | 60% | - | |
| 6 | 2001:978:2:40::3:1 | 6.9ms | - | AS174 | COGENT-174 - Cogent Communications, LLC, US |
Rate-limited ICMPv6: hop 5 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).
tracepath -6
1?: [LOCALHOST] 0.035ms pmtu 1500
1: 2a00:8642:42::3 2.381ms
1: 2a00:8642:42::3 1.618ms
2: gw.friends.steffann.nl 2.573ms
3: 2a00:1ca8:1::194 3.266ms
4: 2a03:3f40::10:41 3.245ms
5: no reply
6: no reply
7: no reply
8: no reply
9: 2001:978:2:40::3:1 6.203ms !N
Resume: pmtu 1500 From ITA host (Karsolink) all blocked
filter likely at: past AS204471 (KARSOLINK) · min PMTU on path: 1500
Path (traceroute + mtr + PTR)
| # | IP / PTR | RTT | mtr loss | AS | AS holder |
|---|---|---|---|---|---|
| 1 | karsolink-01.net.karsolink.com 2a12:d8c0:105a:9001::1 | 0.4ms | 0%* | AS204471 | KARSOLINK - 2S Computers SRL, IT |
| 2 | * | - | 0%* | - | |
| 3 | 2a12:d8c0:101f:6::1 | 10.0ms | 30% | AS204471 | KARSOLINK - 2S Computers 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] 0.030ms pmtu 1500
1: karsolink-01.net.karsolink.com 0.796ms
2: 2a12:d8c0:109f:121::a1 0.676ms
3: 2a12:d8c0:101f:6::1 10.524ms !N
Resume: pmtu 1500 From SLO host (6connect) all blocked
filter likely at: past AS8038 (6CONNECT) · min PMTU on path: 1500
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 | * | - | - | - | |
| 4 | * | - | 0%* | - | |
| 5 | * | - | - | - | |
| 6 | * | - | - | - | |
| 7 | * | - | - | - | |
| 8 | * | - | - | - | |
| 9 | * | - | - | - | |
| 10 | * | - | - | - | |
| 11 | * | - | - | - | |
| 12 | * | - | - | - | |
| 13 | * | - | - | - | |
| 14 | * | - | - | - | |
| 15 | * | - | - | - | |
| 16 | * | - | - | - | |
| 17 | * | - | - | - | |
| 18 | * | - | - | - | |
| 19 | * | - | - | - | |
| 20 | * | - | - | - | |
| 21 | * | - | - | - | |
| 22 | * | - | - | - | |
| 23 | * | - | - | - | |
| 24 | * | - | - | - |
tracepath -6
1?: [LOCALHOST] 0.030ms pmtu 1500
1: fw1-lju.6connect.com 0.469ms
1: fw1-lju.6connect.com 0.429ms
2: no reply
3: no reply
4: no reply
5: no reply
6: no reply
7: no reply
8: no reply
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