AS42882 - SYSUP-AT SysUP ITPI/PARFC 4890 ✓RPKI -ASPA -

AS overview

Test target: 2a00:1510::100 · dns1.sysup.at · address space: mixed · prefixes announced: 1

prefix(es): 2a00:1510::/32

VIX / AAIX / SAIX / TIROL-IX / ERA-IX peering

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

We probed 35 arbitrary IPv6 address(es) inside AS42882's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a02:8384:11:257::2 at hop 15 - that router answers ICMPv6 Echo. This is not in AS42882'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

Vantage points disagree about Type 2 acceptance - transit ASes on one path may be filtering Type 2 even though the destination's stack accepts it on another path:

• SRB host (SOX, Belgrade): Type 2 honored. Forged PTB accepted; next response shrunk. (ICMPv6 Echo + forged PTB)
• DE host (Berlin): Type 2 honored. Forged PTB accepted; next response shrunk. (ICMPv6 Echo + forged PTB)
• DE host (Düsseldorf): Type 2 NOT honored. Forged PTB had no effect (filtered en route or stack ignored it). (ICMPv6 Echo + forged PTB)
• NL host (go6lab): inconclusive: no Echo Reply after PTB (probe 1500B). (ICMPv6 Echo + forged PTB)
• ITA host (Karsolink): Type 2 honored. Forged PTB accepted; next response shrunk. (ICMPv6 Echo + forged PTB)
• SLO host (6connect): Type 2 NOT honored. Forged PTB had no effect (filtered en route or stack ignored it). (ICMPv6 Echo + forged PTB)
• SLO host (T-2): Type 2 NOT honored. Forged PTB had no effect (filtered en route or stack ignored it). (ICMPv6 Echo + forged PTB)

Why they disagree - path-asymmetric Type 2 filtering: Both vantages used the ICMPv6 Echo + forged-PTB method on the same destination IP, but reached different verdicts. The destination's stack is the same in both cases - so the difference is in the path: a transit AS on one route filters our forged Type 2 (or its return ICMPv6 carrying the embedded packet) while the other route delivers it intact. The vantage that says honored shows what the destination's stack actually does; the one that says not honored shows that the path between us and them drops Type 2.

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)'

sudo ip6tables -L INPUT -nv | grep -iE 'icmpv6|packet-too-big'
sudo nft list ruleset 2>/dev/null | grep -A1 'icmpv6'

sudo sysctl net.ipv6.conf.all.accept_redirects net.ipv4.ip_no_pmtu_disc net.ipv6.route.mtu_expires

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)'

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)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1496

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.011ms pmtu 1500
 1:  _gateway                                              0.460ms 
 1:  _gateway                                              0.353ms 
 2:  sox-pn.sox.rs                                         0.522ms 
 3:  2001:7f8:1e:8::3d                                     0.785ms asymm  2 
 4:  2001:67c:128c::699                                   24.513ms asymm  5 
 5:  no reply
 6:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  46.446ms pmtu 1496
 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
     Too many hops: pmtu 1496

From DE host (Berlin)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 4, hop 8 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.028ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.676ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.760ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        1.363ms 
 3:  2003:0:f00::6dc                                       1.817ms 
 4:  no reply
 5:  no reply
 6:  no reply
 7:  no reply
 8:  2a02-8384-0011-0257-0000-0000-0000-0002.static.v6.upcbusiness.at  23.564ms asymm 16 
 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
     Too many hops: pmtu 1500
     Resume: pmtu 1500 

From DE host (Düsseldorf)   echo onlyRFC 4890 ✗

filter likely at: destination AS42882 (SYSUP-AT) · min PMTU on path: 1496

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 14, hop 15 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.021ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.484ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.398ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.287ms 
 3:  no reply
 4:  lag30.core3-dus1.bb.wiit.network                      0.549ms 
 5:  lag0-vl1011.core1-fra-ix.bb.wiit.network              4.446ms 
 6:  lag0-vl1001.core1-nbg-ncd.bb.wiit.network             6.912ms 
 7:  lag0-vl6.core2-nbg-ncd.bb.wiit.network                6.823ms 
 8:  lag0-vl1006.core2-muc2.bb.wiit.network                9.458ms 
 9:  lag0-vl2.core1-muc2.bb.wiit.network                   9.818ms 
10:  2001:7f8:44::20dc:0:1                                10.517ms 
11:  no reply
12:  no reply
13:  no reply
14:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  17.658ms 
15:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  17.806ms pmtu 1496
15:  2a00:1510::1                                         17.615ms 
16:  no reply
17:  no reply
18:  no reply
19:  no reply
20:  no reply
21:  no reply
     Too many hops: pmtu 1496

From NL host (go6lab)   open

filter likely at: (none) · min PMTU on path: 1496

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.048ms pmtu 1496
 1:  2a00:8642:42::2                                       4.734ms 
 1:  2a00:8642:42::2                                       4.458ms 
 2:  gw.friends.steffann.nl                                3.847ms 
 3:  2a00:1ca8:1::194                                      7.199ms 
 4:  2a03:3f40::10:41                                      4.021ms 
 5:  no reply
 6:  2001:730:2800::5474:8001                             37.050ms asymm  8 
 7:  no reply
 8:  2a02-8386-0000-0000-0000-0002-0005-0000.static.v6.upcbusiness.at  36.357ms asymm 13 
 9:  2a02-8386-0000-0000-0000-0001-0096-0001.static.v6.upcbusiness.at 115.934ms asymm 13 
10:  2a02-8386-0000-0000-0000-0096-0023-0001.static.v6.upcbusiness.at  34.129ms asymm 12 
11:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  38.382ms asymm 13 
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
     Too many hops: pmtu 1496
     Resume: pmtu 1496 

From ITA host (Karsolink)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 3, hop 5, hop 7, hop 8, hop 10, hop 13 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.029ms pmtu 1500
 1:  karsolink-01.net.karsolink.com                        0.792ms 
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.919ms 
 3:  no reply
 4:  ae8-202.RT.CLR.MIL.IT.retn.net                        7.954ms asymm  5 
 5:  2001:1900:5:2:2::5b1d                                19.944ms asymm  8 
 6:  lo0.0.edge5.Berlin1.level3.net                       31.526ms asymm  8 
 7:  system.0.ear1.Frankfurt18.level3.net                 17.152ms 
 8:  2003:0:f00::e0a                                      17.614ms asymm  7 
 9:  no reply
10:  2003:0:fe00:e::2                                     28.918ms asymm  8 
11:  no reply
12:  no reply
13:  2a02-8384-0011-0257-0000-0000-0000-0002.static.v6.upcbusiness.at  30.263ms asymm 11 
14:  no reply
15:  no reply
16:  no reply
17:  no reply
18:  no reply
19:  no reply
20:  no reply
21:  no reply
     Too many hops: pmtu 1500
     Resume: pmtu 1500 

From SLO host (6connect)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1496

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.016ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.719ms 
 1:  fw1-lju.6connect.com                                  0.511ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  1.135ms 
 4:  2a03:a100:0:201:1::1                                  1.072ms pmtu 1500
 4:  e0-1.core1.lju1.he.net                                2.098ms 
 5:  100ge0-0-0-5.core1.vie1.he.net                        8.180ms 
 6:  2a02-8383-0000-1000-0000-0000-0006-0000.static.v6.upcbusiness.at   7.870ms 
 7:  no reply
 8:  no reply
 9:  no reply
10:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at   9.987ms 
11:  no reply
12:  no reply
13:  no reply
14:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  10.191ms pmtu 1496
14:  no reply
15:  no reply
16:  no reply
17:  no reply
18:  no reply
19:  no reply
20:  no reply
21:  no reply

From SLO host (T-2)   openRFC 4890 ✗

filter likely at: (none) · min PMTU on path: 1496

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 11 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.020ms pmtu 1500
 1:  2a01:261:313:b814::1                                  0.779ms 
 1:  no reply
 2:  2a01:260:1::225                                       4.447ms 
 3:  2a01-260-1-1--9c.core6.t-2.net                        3.472ms 
 4:  2a01-260-1-1--25.core6.t-2.net                        6.066ms 
 5:  2a01-260-1-1--c.core6.t-2.net                         4.991ms asymm  4 
 6:  atwre21p401.as8412.net                               10.739ms asymm  8 
 7:  no reply
 8:  no reply
 9:  2a02-8384-0011-0257-0000-0000-0000-0002.static.v6.upcbusiness.at  12.582ms asymm 10 
10:  2a02-8384-0011-0258-0000-0000-0000-0002.static.v6.upcbusiness.at  13.127ms pmtu 1496
10:  2a00:1510::1                                         13.316ms 
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
     Too many hops: pmtu 1496