AS56488 - EISIT Eis S.r.lRFC 4890 ✓RPKI ✓ 2/2ASPA ✓

AS overview

Test target: 2a12:2544::1 · static prefix probe · address space: unknown · prefixes announced: 2

prefix(es): 2a12:2544::/30, 2a12:2540::/30

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

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

At least one router inside AS56488's announced prefix replied during the random-target probe. Hop(s): 2a12:2540:1::2, 2a12:2540:1::3, 2a12:2540::1, 2a12:2544::2. These are candidate targets for direct testing.

ICMPv6 Type 2 (Packet Too Big) acceptance - active test

Type 2 honored. Forged ICMPv6 PTB (MTU=1280) was accepted by the destination's stack: the next 1500-byte Echo Reply arrived split into 2 fragments via the IPv6 Fragment Header.
method: ICMPv6 Echo + forged PTB, tested 2026-09-23T12:08:56Z

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: 1500

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.011ms pmtu 1500
 1:  _gateway                                              0.524ms 
 1:  _gateway                                              0.491ms 
 2:  sox-pn.sox.rs                                         0.459ms 
 3:  2001:7f8:1e:8::3d                                     1.127ms asymm  2 
 4:  ae8-930.RT.IRX.VIE.AT.retn.net                       12.962ms asymm  3 
 5:  RT.VSX.PDA.IT.retn.net                               20.863ms asymm  4 
 6:  GW-Aruba.retn.net                                    32.346ms asymm  7 
 7:  no reply
 8:  er2-hu0-0-0-21.ip6.it3.aruba.it                      29.351ms asymm  7 
 9:  gw-dc1.bgy.eis.it                                    29.190ms reached
     Resume: pmtu 1500 hops 9 back 8 

From DE host (Berlin)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 6 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.029ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  7.932ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  1.733ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        1.205ms 
 3:  retn.bcix.de                                         10.872ms asymm  5 
 4:  RT.VSX.PDA.IT.retn.net                               26.195ms asymm  5 
 5:  GW-Aruba.retn.net                                    29.018ms asymm 13 
 6:  cr1-hu0-0-0-3-714.ip6.it3.aruba.it                   26.134ms asymm 12 
 7:  er2-hu0-0-0-20.ip6.it3.aruba.it                      23.363ms asymm 13 
 8:  gw-dc1.bgy.eis.it                                    23.643ms reached
     Resume: pmtu 1500 hops 8 back 14 

From DE host (Düsseldorf)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 13, hop 14 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.060ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.436ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.442ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.373ms 
 3:  no reply
 4:  lag30.core3-dus1.bb.wiit.network                      0.654ms 
 5:  lag0-vl1011.core1-fra-ix.bb.wiit.network              4.446ms 
 6:  lag0-vl1001.core1-nbg-ncd.bb.wiit.network             6.987ms 
 7:  lag0-vl6.core2-nbg-ncd.bb.wiit.network                6.905ms 
 8:  lag0-vl1006.core2-muc2.bb.wiit.network                9.627ms 
 9:  lag0-vl1009.core1-muc-eq3.bb.wiit.network             9.817ms 
10:  lag0-vl1001.core1-pda-vsix.bb.wiit.network           20.336ms 
11:  lag0-vl1001.core1-mil-mix.bb.wiit.network            20.541ms asymm  9 
12:  lag0-vl5.core3-mil-irid.bb.wiit.network              20.457ms asymm  8 
13:  no reply
14:  no reply
15:  er2-hu0-0-0-20.ip6.it3.aruba.it                      21.972ms asymm 12 
16:  gw-dc1.bgy.eis.it                                    22.262ms reached
     Resume: pmtu 1500 hops 16 back 13 

From NL host (go6lab)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.053ms pmtu 1500
 1:  2a00:8642:42::2                                       3.179ms 
 1:  2a00:8642:42::2                                       2.034ms 
 2:  gw.friends.steffann.nl                                5.375ms 
 3:  2a00:1ca8:1::194                                      6.299ms 
 4:  2a03:3f40::10:33                                      6.116ms 
 5:  ams-ix.retn.net                                       8.138ms asymm  7 
 6:  RT.VSX.PDA.IT.retn.net                               23.051ms 
 7:  GW-Aruba.retn.net                                    32.404ms asymm 11 
 8:  cr2-hu0-0-0-3-713.ip6.it3.aruba.it                   27.710ms asymm  9 
 9:  er2-hu0-0-0-21.ip6.it3.aruba.it                      22.985ms asymm 10 
10:  gw-dc1.bgy.eis.it                                    32.920ms reached
     Resume: pmtu 1500 hops 10 back 11 

From ITA host (Karsolink)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.033ms pmtu 1500
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.767ms 
 3:  2a12:d8c0:101f:103::1                                 8.731ms 
 4:  no reply
 5:  no reply
 6:  er2-hu0-0-0-20.ip6.it3.aruba.it                      11.595ms asymm  7 
 7:  gw-dc1.bgy.eis.it                                    12.099ms reached
     Resume: pmtu 1500 hops 7 back 8 

From SLO host (6connect)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 4, hop 6, hop 8, hop 9 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.022ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.789ms 
 1:  fw1-lju.6connect.com                                  0.649ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  1.128ms 
 4:  2a03:a100:0:201:1::1                                  1.061ms pmtu 1500
 4:  e0-1.core1.lju1.he.net                                2.103ms 
 5:  no reply
 6:  port-channel1.core1.zag2.he.net                       4.455ms 
 7:  no reply
 8:  no reply
 9:  no reply
10:  er2-hu0-0-0-21.ip6.it3.aruba.it                      13.271ms asymm  9 
11:  gw-dc1.bgy.eis.it                                    12.020ms reached
     Resume: pmtu 1500 hops 11 back 10 

From SLO host (T-2)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: 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:  2a01:261:313:b814::1                                  0.876ms 
 1:  no reply
 2:  2a01:260:1::225                                       4.362ms 
 3:  2a01-260-1-1--9c.core6.t-2.net                        2.898ms 
 4:  no reply
 5:  port-channel1.core1.zag2.he.net                      10.853ms asymm  7 
 6:  port-channel1.core1.zag2.he.net                      10.511ms asymm  7 
 7:  no reply
 8:  no reply
 9:  er2-hu0-0-0-21.ip6.it3.aruba.it                      18.207ms 
10:  ???                                                  17.992ms reached
     Resume: pmtu 1500 hops 10 back 10