AS57264 OPTICONN-IT OPTICONN SRL

IPv6 prefix announced, but nothing inside is responding yet. AS57264 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: 2a0d:2640::1 · (no live host found) · address space: PA · prefixes announced: 1

prefix(es): 2a0d:2640::/29

RPKI & ASPA

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

Prefix	RPKI state	Reason	Covering VRP(s)
`2a0d:2640::/29`	✓ valid	matched VRP (correct origin, length within maxLength)	AS57264 /29 maxLen 29 (ripe)

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

We probed 15 arbitrary IPv6 address(es) inside AS57264's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a03:b020:1:4::b at hop 23 - that router answers ICMPv6 Echo. This is not in AS57264'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 2026-05-25T12:36:31Z

Failure detail — what to grep in your logs

vantage	our source	your target	method	result	tested (UTC)
go6lab	`2a00:8642:42::75`	`2a0d:2640::1`	`icmp6-echo`	no_echo	2026-05-25T12:36:31Z
karsolink	`2a12:d8c0:105a:9001::a154`	`2a0d:2640::1`	`icmp6-echo`	no_echo	2026-05-25T12:47:41Z
odin	`2607:fae0:a000::42`	`2a0d:2640::1`	`icmp6-echo`	no_echo	2026-05-25T12:36:04Z

Attempt log (go6lab):

icmp6-echo → no_echo: no Echo Reply to 1300-byte probe
dns-tcp → no_tcp: connect failed: [Errno 101] Network is unreachable
tls → no_tcp: TLS connect failed
http → no_tcp: tcp/80 not open

Attempt log (karsolink):

icmp6-echo → no_echo: no Echo Reply to 1300-byte probe
dns-tcp → no_tcp: connect failed: [Errno 101] Network is unreachable
tls → no_tcp: TLS connect failed
http → no_tcp: tcp/80 not open

Attempt log (odin):

icmp6-echo → no_echo: no Echo Reply to 1300-byte probe
dns-tcp → no_tcp: connect failed: [Errno 101] Network is unreachable
tls → no_tcp: TLS connect failed
http → 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 AS41327 (FIBERTELECOM-AS) · min PMTU on path: 1500

0/4

Echo small (56B) -

0/4

Echo 1500B (DF) -

Type 1 dest-unreach

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	2a00:8642:42::3	1.1ms	0%	AS203993	STEFFANN-DC-AS - S.J.M. Steffann, NL
2	gw.friends.steffann.nl 2a00:8642:1000:f000::1	1.7ms	0%*	AS203993	STEFFANN-DC-AS - S.J.M. Steffann, NL
3	speed-ix.fibertelecom.it 2001:7f8:b7::a504:1327:1	3.1ms	0%	-	NA
4	2a03:b020::226	19.1ms	0%	AS41327	FIBERTELECOM-AS - Fiber Telecom S.p.A., IT
5	2a03:b020:1:4::b	18.9ms	0%	AS41327	FIBERTELECOM-AS - Fiber Telecom S.p.A., IT

tracepath -6

 1?: [LOCALHOST]                        0.037ms pmtu 1500
 1:  2a00:8642:42::3                                       1.619ms 
 1:  2a00:8642:42::3                                       1.479ms 
 2:  gw.friends.steffann.nl                                2.484ms 
 3:  speed-ix.fibertelecom.it                              4.039ms 
 4:  2a03:b020::226                                       19.853ms 
 5:  2a03:b020:1:4::b                                     19.522ms !N
     Resume: pmtu 1500

From ITA host (Karsolink) transit only unreachable

filter likely at: past AS41327 (FIBERTELECOM-AS) · min PMTU on path: 1500

0/4

Echo small (56B) -

0/4

Echo 1500B (DF) -

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	0.3ms	0%*	AS204471	KARSOLINK - 2S Computers SRL, IT
2	2a12:d8c0:109f:121::a1	0.5ms	0%*	AS204471	KARSOLINK - 2S Computers SRL, IT
3	2a12:d8c0:101f:6::1	10.0ms	-	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:b020:1:4::b	10.0ms	0%	AS41327	FIBERTELECOM-AS - Fiber Telecom S.p.A., IT

tracepath -6

 1?: [LOCALHOST]                        0.028ms pmtu 1500
 1:  karsolink-01.net.karsolink.com                        0.670ms 
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.819ms 
 3:  2a12:d8c0:101f:6::1                                  10.381ms 
 4:  2a03:b020:1:51::a                                    10.847ms 
 5:  2a03:b020:1:4::b                                     10.755ms !N
     Resume: pmtu 1500

From SLO host (6connect) transit only unreachable

filter likely at: past AS41327 (FIBERTELECOM-AS) · min PMTU on path: 1500

0/4

Echo small (56B) -

0/4

Echo 1500B (DF) -

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	*	-	0%*	-
3	2a03:a100:0:201:1::1	0.7ms	50%	AS56635	XENYA - XENYA inzeniring, proizvodnja in trgovina, d.o.o. Ljubljana, SI
4	e0-1.core1.lju1.he.net 2001:470:1:5be::1	2.2ms	40%	AS6939	HURRICANE - Hurricane Electric LLC, US
5	100ge0-0-0-5.core1.vie1.he.net 2001:470:0:578::1	8.4ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
6	e0-35.core2.muc1.he.net 2001:470:0:41d::2	12.3ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
7	ipv6.de-cix.muc.as41327.fibertelecom.com 2001:7f8:44::a16f:0:1	17.4ms	0%	-	NA
8	2a03:b020::226	25.8ms	0%	AS41327	FIBERTELECOM-AS - Fiber Telecom S.p.A., IT
9	2a03:b020:1:4::b	25.6ms	0%	AS41327	FIBERTELECOM-AS - Fiber Telecom S.p.A., IT

Rate-limited ICMPv6: hop 3, hop 4 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.018ms pmtu 1500
 1:  fw1-lju.6connect.com                                  0.481ms 
 1:  fw1-lju.6connect.com                                  0.397ms 
 2:  no reply
 3:  no reply
 4:  e0-1.core1.lju1.he.net                                1.825ms 
 5:  100ge0-0-0-5.core1.vie1.he.net                        9.110ms 
 6:  e0-35.core2.muc1.he.net                              12.072ms 
 7:  ipv6.de-cix.muc.as41327.fibertelecom.com             17.746ms asymm 10 
 8:  2a03:b020::226                                       26.269ms asymm 10 
 9:  2a03:b020:1:4::b                                     25.854ms !N
     Resume: pmtu 1500