AS215536 AS-PPNET6 Patrizio Palumbo

AS overview

Test target: 2a0e:b107:12df::1 · static prefix probe · address space: unknown · prefixes announced: 2

prefix(es): 2a0e:b107:12df::/48, 2a0e:b107:12db::/48

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 / hostname	Source	SRB host (SOX, Belgrade)					DE host (Berlin)					DE host (Düsseldorf)					NL host (go6lab)					ITA host (Karsolink)					SLO host (6connect)					SLO host (T-2)
Target IP / hostname	Source	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached	ping	1500B	:80	:443	reached
`2a0e:b107:12df::1`	prb	✓	✗	open	refused	✓	✓	✗	open	refused	✓	✓	✗	open	refused	✓	✓	✗	open	?	✓	✓	✗	open	refused	✓	✓	✗	open	refused	✓	✓	✗	open	refused	✓

MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO peering

Not an MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO member, but our traceroute path crosses the MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO LAN from ITA host (Karsolink) - reached via an MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO-resident transit operator.

RPKI & ASPA

1 of 2 prefix(es) covered by a valid ROA, 1 not-found.

Prefix	RPKI state	Reason	Covering VRP(s)
`2a0e:b107:12df::/48`	✓ valid	matched VRP (correct origin, length within maxLength)	AS215536 /48 maxLen 48 (ripe)
`2a0e:b107:12db::/48`	- not-found	no covering VRP

ASPA: this AS has published an ASPA record listing 1 upstream provider(s) that are authorized to propagate routes from it: AS211358. Routes from this AS that arrive via any other upstream are considered ASPA-invalid by validators that enforce ASPA.

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

We probed 60 arbitrary IPv6 address(es) inside AS215536's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a0e:b107:12d3:b00b:7612::2 at hop 25 - that router answers ICMPv6 Echo. This is not in AS215536'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 not honored. Forged ICMPv6 PTB (MTU=1280) had no effect: the next 1500-byte Echo Reply still arrived whole (1360 B, no Fragment Header). PMTUD does not work toward this address from us.
method: ICMPv6 Echo + forged PTB, tested 2026-09-23T12:07:51Z

Failure detail - what to grep in your logs

vantage	our source	your target	method	result	tested (UTC)
belgrade	`2a09:ab81::91`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:51Z
berlin	`2a06:d1c1:10b::cccc`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:49Z
duseldorf	`2a06:d1c1:10d::aaaa`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:47Z
go6lab	`2a00:8642:42::75`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:09:30Z
karsolink	`2a12:d8c0:105a:9001::a154`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:49Z
odin	`2607:fae0:a000::42`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:47Z
t2	`2a01:261:313:b814:2a0:98ff:fe5b:13e4`	`2a0e:b107:12df::1`	`icmp6-echo`	not_honored	2026-09-23T12:07:50Z

Attempt log (belgrade):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (berlin):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (duseldorf):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (go6lab):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: timed out
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (karsolink):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (odin):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

Attempt log (t2):

icmp6-echo → not_honored (reply shrank 1360→1360 B)
dns-tcp → no_tcp: connect failed: [Errno 111] Connection refused
tls → no_tcp: TLS connect failed
http → inconclusive (reply 522 B before PTB): natural max segment 522B already <= 1220B; nothing to shrink

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 1360 B; after, it was 1360 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

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.
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.
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 (2026-09-23T12:07:51Z) 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.

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 ↗

● SRB host (SOX, Belgrade)
● DE host (Berlin)
● DE host (Düsseldorf)
● NL host (go6lab)
● ITA host (Karsolink)
● SLO host (6connect)
● SLO host (T-2)
── solid line = echo reply, PTB honored (clean reach)
— — dashed line = echo reply but PTB not honored (RFC 4890 violation)
no line = no echo reply (never reached)
◉ target: green = clean, amber = reachable-but-violation / unreachable
⚠ suspected drop AS
⋯ silent (unanswered) hops
● IXP hop

From SRB host (SOX, Belgrade) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 42.8ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	2a09:ab81::1	0.2ms	0%*	AS60733	PERKE-NET - ZORAN PEROVIC trading as Agencija Perke.NET, RS
2	sox-pn.sox.rs 2001:7f8:1e:8::3a	0.3ms	0%	AS13004	SOX - Serbian Open Exchange DOO, RS
3	2001:7f8:1e:8::3d	0.4ms	0%	AS13004	SOX - Serbian Open Exchange DOO, RS
4	2001:67c:128c::699	17.9ms	0%	-	NA
5	2001:67c:128c::39e	19.5ms	0%	-	NA
6	*	-	-	-
7	*	-	-	-
8	2a12:3200:f000::222	36.7ms	0%	AS6204	ZET-NET - INTERKVM HOST SRL, RO
9	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	34.6ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
10	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	43.0ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
11	2a0e:b107:12df::1	42.9ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

tracepath -6

 1?: [LOCALHOST]                        0.015ms pmtu 1500
 1:  _gateway                                              0.523ms 
 1:  _gateway                                              0.393ms 
 2:  sox-pn.sox.rs                                         0.414ms 
 3:  2001:7f8:1e:8::3d                                     0.730ms asymm  2 
 4:  2001:67c:128c::699                                   18.262ms 
 5:  2001:67c:128c::39e                                   19.076ms asymm  3 
 6:  no reply
 7:  no reply
 8:  2a12:3200:f000::222                                  36.855ms asymm  5 
 9:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             34.655ms 
10:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             36.431ms pmtu 1476
10:  router.eu.10GbE.ppnetworks.it                        43.099ms 
11:  2a0e:b107:12df::1                                    45.974ms reached
     Resume: pmtu 1476 hops 11 back 11

From DE host (Berlin) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 30.1ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	xe-0-0-13-178.gw01.ber01.as59645.net 2a06:d1c1:100:b::1	0.3ms	0%*	AS59645	WYBT-NET - Tobias Fiebig, DE
2	ae0-2453.cr10.ber01.lwlcom.net 2a06:d1c0::dead:beef:1c02	0.7ms	0%*	AS59645	WYBT-NET - Tobias Fiebig, DE
3	ae0-150.cr10.fra01.lwlcom.net 2a00:c380:b200:230::174	10.1ms	0%	AS50629	LWLCOM - LWLcom GmbH, DE
4	ae0-100.cr10.fra02.lwlcom.net 2a00:c380:b200:230::215	10.2ms	0%	AS50629	LWLCOM - LWLcom GmbH, DE
5	ae0-10.cr10.fra06.lwlcom.net 2a00:c380:b200:230::236	9.9ms	0%	AS50629	LWLCOM - LWLcom GmbH, DE
6	*	-	-	-
7	*	-	-	-
8	*	-	-	-
9	2a12:3200:f000::222	21.4ms	0%	AS6204	ZET-NET - INTERKVM HOST SRL, RO
10	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	21.5ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
11	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	30.2ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
12	2a0e:b107:12df::1	30.1ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

tracepath -6

 1?: [LOCALHOST]                        0.040ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.452ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.399ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        0.810ms 
 3:  ae0-150.cr10.fra01.lwlcom.net                        10.176ms asymm  7 
 4:  ae0-100.cr10.fra02.lwlcom.net                        10.662ms asymm  8 
 5:  ae0-10.cr10.fra06.lwlcom.net                         10.247ms asymm  7 
 6:  no reply
 7:  no reply
 8:  no reply
 9:  2a12:3200:f000::222                                  21.837ms asymm  5 
10:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             21.740ms asymm  5 
11:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             21.629ms pmtu 1476
11:  router.eu.10GbE.ppnetworks.it                        29.821ms asymm  6 
12:  2a0e:b107:12df::1                                    30.291ms reached
     Resume: pmtu 1476 hops 12 back 7

From DE host (Düsseldorf) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 20.8ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	xe-0-0-12-142.gw01.dus01.as59645.net 2a06:d1c1:100:d::1	0.2ms	0%*	AS59645	WYBT-NET - Tobias Fiebig, DE
2	ipv6.decix-dusseldorf.core1.dus1.he.net 2001:7f8:9e::1b1b:0:1	5.9ms	0%	-	NA
3	*	-	-	-
4	be47.core3.ams1.he.net 2001:470:e:12::2	9.3ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
5	*	-	20%	-
6	be4.core2.lon3.he.net 2001:470:e:41::2	14.2ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
7	*	-	-	-
8	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	12.5ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
9	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	21.1ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
10	2a0e:b107:12df::1	21.3ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

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:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.486ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.344ms 
 2:  ipv6.decix-dusseldorf.core1.dus1.he.net               7.289ms asymm  3 
 3:  no reply
 4:  be47.core3.ams1.he.net                                9.645ms 
 5:  be3.core4.lon2.he.net                                14.463ms 
 6:  be4.core2.lon3.he.net                                13.499ms 
 7:  no reply
 8:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             12.599ms asymm  4 
 9:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             13.275ms pmtu 1476
 9:  router.eu.10GbE.ppnetworks.it                        24.522ms asymm  5 
10:  2a0e:b107:12df::1                                    20.978ms reached
     Resume: pmtu 1476 hops 10 back 6

From NL host (go6lab) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 22.0ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	2a00:8642:42::2	4.6ms	0%	AS203993	GNA-DC1-AS - S.J.M. Steffann, NL
2	*	-	0%*	-
3	2a00:1ca8:1::194	3.2ms	0%	AS50673	Serverius-as - Serverius Holding B.V., NL
4	2a03:3f40::10:33	6.1ms	0%	AS50673	Serverius-as - Serverius Holding B.V., NL
5	et-0-0-3.lon2-m140-bdr2.as215638.net 2001:7f8:1:0:a500:21:5638:1	13.5ms	0%	-	NA
6	*	-	-	-
7	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	12.3ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
8	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	14.3ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
9	2a06:a005:753:ffff:8248::2	21.3ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
10	2a0e:b107:12df::1	20.5ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

tracepath -6

 1?: [LOCALHOST]                        0.024ms pmtu 1476
 1:  2a00:8642:42::2                                       1.493ms 
 1:  2a00:8642:42::2                                       2.793ms 
 2:  no reply
 3:  2a00:1ca8:1::194                                      3.056ms 
 4:  2a03:3f40::10:33                                      7.661ms 
 5:  et-0-0-3.lon2-m140-bdr2.as215638.net                 14.076ms 
 6:  no reply
 7:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it            807.188ms 
 8:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             13.141ms asymm  7 
 9:  2a06:a005:753:ffff:8248::2                           19.696ms asymm  8 
10:  2a0e:b107:12df::1                                    19.438ms reached
     Resume: pmtu 1476 hops 10 back 9

From ITA host (Karsolink) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 36.8ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	*	-	0%*	-
2	*	-	0%*	-
3	2a12:d8c0:101f:103::1	8.5ms	-	AS204471	KARSOLINK - 2S Computers SRL, IT
4	interkvm-AS6204.mix-it.net @MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO 2001:7f8:b:100:1d1:a5d0:6204:192	8.7ms	0%	-	NA
5	*	-	-	-
6	*	-	-	-
7	2a12:3200:f000::222	28.0ms	0%	AS6204	ZET-NET - INTERKVM HOST SRL, RO
8	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	28.1ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
9	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	38.1ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
10	2a0e:b107:12df::1	37.9ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

tracepath -6

 1?: [LOCALHOST]                        0.055ms pmtu 1500
 1:  karsolink-01.net.karsolink.com                        0.735ms 
 1:  karsolink-01.net.karsolink.com                        0.641ms 
 2:  2a12:d8c0:109f:121::a1                                0.674ms 
 3:  no reply
 4:  interkvm-AS6204.mix-it.net                            9.269ms 
 5:  no reply
 6:  no reply
 7:  2a12:3200:f000::222                                  28.290ms 
 8:  rs.as211358.uk.lonap.10gbe.ppnetworks.it             28.522ms asymm 11 
 9:  rs.as211358.uk.lonap.10gbe.ppnetworks.it             29.221ms pmtu 1476
 9:  router.eu.10gbe.ppnetworks.it                        37.504ms asymm 12 
10:  2a0e:b107:12df::1                                    36.855ms reached
     Resume: pmtu 1476 hops 10 back 13

From SLO host (6connect) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 35.2ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

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	*	-	-	-
3	2a03:a100:0:201:1::1	1.6ms	0%	AS56635	XENYA - XENYA inzeniring, proizvodnja in trgovina, d.o.o. Ljubljana, SI
4	*	-	30%	-
5	100ge0-0-0-5.core1.vie1.he.net 2001:470:0:578::1	9.0ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
6	be3.core1.prg1.he.net 2001:470:e:a7::1	11.6ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
7	be8.core4.fra1.he.net 2001:470:e:1e::1	20.1ms	20%	AS6939	HURRICANE - Hurricane Electric LLC, US
8	be2.core3.ams1.he.net 2001:470:e:38::1	23.9ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
9	be3.core4.lon2.he.net 2001:470:e:49::2	31.4ms	10%	AS6939	HURRICANE - Hurricane Electric LLC, US
10	be4.core2.lon3.he.net 2001:470:e:41::2	29.4ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
11	*	-	-	-
12	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	27.0ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
13	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	35.5ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
14	2a0e:b107:12df::1	35.3ms	0%	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

Rate-limited ICMPv6: hop 4, hop 7, hop 9 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.031ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.551ms 
 1:  fw1-lju.6connect.com                                  0.529ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  1.102ms 
 4:  2a03:a100:0:201:1::1                                  0.858ms pmtu 1500
 4:  e0-1.core1.lju1.he.net                                2.112ms 
 5:  100ge0-0-0-5.core1.vie1.he.net                        8.383ms 
 6:  be3.core1.prg1.he.net                                14.135ms 
 7:  be8.core4.fra1.he.net                                19.701ms 
 8:  be2.core3.ams1.he.net                                25.799ms 
 9:  be3.core4.lon2.he.net                                29.866ms 
10:  be4.core2.lon3.he.net                                29.693ms asymm  8 
11:  no reply
12:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             27.515ms asymm  9 
13:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             26.951ms pmtu 1476
13:  router.eu.10GbE.ppnetworks.it                        36.202ms asymm 10 
14:  2a0e:b107:12df::1                                    36.833ms reached
     Resume: pmtu 1476 hops 14 back 11

From SLO host (T-2) echo onlyRFC 4890 ✗

filter likely at: destination AS215536 (AS-PPNET6) · min PMTU on path: 1476

4/4

Echo small (56B) 42.1ms

0/4

Echo 1500B (DF) -

yes

Type 1 dest-unreach

443,80

TCP responds on

Path (traceroute + mtr + PTR)

#	IP / PTR	RTT	mtr loss	AS	AS holder
1	2a01:261:313:b814::1	0.6ms	0%*	AS34779	T-2-AS - T-2, d.o.o., SI
2	2a01:260:1::225	2.2ms	0%*	AS34779	T-2-AS - T-2, d.o.o., SI
3	2a01-260-1-1--9c.core6.t-2.net 2a01:260:1:1::9c	2.6ms	0%*	AS34779	T-2-AS - T-2, d.o.o., SI
4	2a01-260-1-1--38.core6.t-2.net 2a01:260:1:1::38	2.3ms	-	AS34779	T-2-AS - T-2, d.o.o., SI
5	100ge0-0-0-31.core1.vie1.he.net 2001:470:0:4a8::1	12.2ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
6	be3.core1.prg1.he.net 2001:470:e:a7::1	15.0ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
7	*	-	20%	-
8	be2.core3.ams1.he.net 2001:470:e:38::1	30.4ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
9	be2.core3.ams1.he.net 2001:470:e:38::1	32.7ms	20%	AS6939	HURRICANE - Hurricane Electric LLC, US
10	be4.core2.lon3.he.net 2001:470:e:41::2	35.4ms	0%	AS6939	HURRICANE - Hurricane Electric LLC, US
11	be4.core2.lon3.he.net 2001:470:e:41::2	35.2ms	-	AS6939	HURRICANE - Hurricane Electric LLC, US
12	RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it 2a06:a005:753::1	34.3ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
13	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	41.9ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
14	router.eu.10GbE.ppnetworks.it 2a0e:b107:12d3::1	41.1ms	0%	AS211358	AS-IPV6GO - Patrizio Palumbo, IT
15	2a0e:b107:12df::1	46.8ms	-	AS215536	AS-PPNET6 - Patrizio Palumbo, IT

Rate-limited ICMPv6: hop 7, hop 9 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.027ms pmtu 1500
 1:  2a01:261:313:b814::1                                  0.830ms 
 2:  2a01:260:1::225                                       4.156ms 
 3:  2a01-260-1-1--9c.core6.t-2.net                        3.281ms 
 4:  2a01-260-1-1--38.core6.t-2.net                        2.716ms asymm  3 
 5:  100ge0-0-0-31.core1.vie1.he.net                      12.704ms 
 6:  100ge0-0-0-31.core1.vie1.he.net                      12.780ms asymm  5 
 7:  be8.core4.fra1.he.net                                36.972ms 
 8:  be2.core3.ams1.he.net                                33.311ms asymm  6 
 9:  be2.core3.ams1.he.net                                31.734ms asymm  6 
10:  be3.core4.lon2.he.net                                37.897ms asymm  6 
11:  be4.core2.lon3.he.net                                35.351ms asymm  5 
12:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             34.413ms asymm  6 
13:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             33.855ms asymm  6 
14:  RS.AS211358.uk.LoNAP.10GbE.ppnetworks.it             34.706ms pmtu 1476
14:  2a0e:b107:12df::1                                    47.228ms reached
     Resume: pmtu 1476 hops 14 back 8