[ITNOG] GTT: congestione giornaliera Milano

Lukas Tribus lukas@ltri.eu
Lun 7 Feb 2022 15:22:30 CET


Buon giorno,


vi informo, magari a qualcuno serve questa informazione, che da una
settimana ca, riscontriamo congestione giornaliera sulla rete GTT fra
Francoforte e Milano.

La congestione inizia nel primo pomeriggio e incrementa pian piano,
con un peak la sera (classico comportamento congestione verso
eyeball). I clienti di transito di GTT a Milano sono impattati. Il
packet-loss misurato domenica sera era intorno ai 30% con 200ms di
latenza. Nei giorni scorsi i peak erano intorno ai 11~12% PL con
latenza di oltre 100ms.

La direzione della congestione è da Francoforte verso Milano, questo è
stato confermato con vari metodi (incluso rerouting di traffico,
Hetzner per esempio ha spostato traffico verso i prefissi di TWT da
GTT su NTT, workaround che funziona ma ovviamente solo per TWT).


Per misurare in tempo reale (da Hetzner):

Smokeping (vari destinazioni che evidenziano packet-loss e latenza,
verso le P2P fra GTT e i suoi clienti ma anche host in quelli reti):
https://smoke.ltri.eu/smokeping/smokeping.cgi?target=External.GTT

LG dallo stesso host che fa le misure:
https://lg.ltri.eu/


MTR:

Host 77.43.16.1 (Irideos/ex MC Link) 06/02 20:16 (30% PL, 200ms latenza)

lukas@htznr2:~$ mtr -rs1000 -c1000 77.43.16.1
Start: 2022-02-06T20:16:34+0100
HOST: htznr2                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- _gateway                   0.0%  1000    5.9   4.8   2.4  24.5   1.4
  2.|-- 10114.your-cloud.host      0.0%  1000    0.4   0.3   0.2   4.8   0.2
  3.|-- ???                       100.0  1000    0.0   0.0   0.0   0.0   0.0
  4.|-- 85-10-250-153.clients.you  0.0%  1000    1.2   4.9   0.8  88.6  11.7
  5.|-- spine12.cloud1.nbg1.hetzn  0.0%  1000    1.0   4.5   0.8  72.9  10.7
  6.|-- 213-239-239-121.clients.y  0.1%  1000    0.8   2.1   0.4  34.1   3.5
  7.|-- core1.fra.hetzner.com      0.0%  1000   28.5  12.4   3.5  50.1   8.1
  8.|-- ae18.cr6-fra2.ip4.gtt.net  0.0%  1000    4.1   6.7   3.6 497.9  18.3
  9.|-- et-5-1-0.cr0-mil2.ip4.gtt 29.6%  1000  199.6 200.9 163.2 252.7   7.3
 10.|-- alpikom-gw.ip4.gtt.net    30.1%  1000  200.8 196.6 165.5 213.0   5.1
 11.|-- gw2-mi-te0100.mclink-net. 31.2%  1000  213.1 211.0 177.5 223.7   5.2
 12.|-- gw2-rm-gi0001.mclink-net. 30.9%  1000  207.6 205.7 178.3 227.8   5.5
 13.|-- 213.21.132.39             29.7%  1000  206.3 205.9 174.7 223.1   5.4
 14.|-- 213.21.132.69             30.6%  1000  212.1 208.7 176.0 225.4   5.8
 15.|-- 213.21.130.142            32.5%  1000  207.3 205.1 169.0 291.7   7.8
 16.|-- net77-43-16-001.mclink.it 29.2%  1000  213.6 212.2 174.3 284.2   7.1
lukas@htznr2:~$


Host 77.43.16.1 (Irideos/ex MC Link) 07/02 00:30 (qua tutto ok)

lukas@htznr2:~$ mtr -rs1000 -c1000 77.43.16.1
Start: 2022-02-07T00:30:15+0100
HOST: htznr2                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- _gateway                   0.0%  1000    5.7   4.8   2.4  26.1   1.6
  2.|-- 10114.your-cloud.host      0.0%  1000    0.4   0.3   0.2   2.5   0.2
  3.|-- ???                       100.0  1000    0.0   0.0   0.0   0.0   0.0
  4.|-- 85-10-250-153.clients.you  0.0%  1000    1.2   4.6   0.8 101.5  11.3
  5.|-- spine12.cloud1.nbg1.hetzn  0.0%  1000   24.9   4.1   0.8  81.3  10.5
  6.|-- 213-239-239-121.clients.y  0.0%  1000    0.7   1.9   0.4  35.9   3.5
  7.|-- core1.fra.hetzner.com      0.0%  1000    3.7   5.6   3.5  39.8   4.3
  8.|-- ae18.cr6-fra2.ip4.gtt.net  0.0%  1000    3.8   6.4   3.5  89.0   8.8
  9.|-- et-5-1-0.cr0-mil2.ip4.gtt  0.0%  1000   18.9  19.3  18.3  74.3   4.2
 10.|-- alpikom-gw.ip4.gtt.net     0.0%  1000   18.8  18.8  18.6  23.5   0.3
 11.|-- gw2-mi-te0100.mclink-net.  0.0%  1000   33.3  33.1  32.9  40.4   0.4
 12.|-- gw2-rm-gi0001.mclink-net.  0.0%  1000   30.3  28.2  27.9  79.8   1.9
 13.|-- 213.21.132.39              0.0%  1000   28.2  28.1  27.9  66.6   1.5
 14.|-- 213.21.132.69              0.0%  1000   27.7  27.6  27.4  34.9   0.4
 15.|-- 213.21.130.142             0.0%  1000   27.5  28.1  27.3 220.7   8.4
 16.|-- net77-43-16-001.mclink.it  0.0%  1000   30.8  31.4  30.4 148.9   6.7
lukas@htznr2:~$

Host 77.43.16.1 (Irideos/ex MC Link) 07/02 14:36 (3% PL, 76ms latenza)

lukas@htznr2:~$ mtr -rs1000 -c1000 77.43.16.1
Start: 2022-02-07T14:36:23+0100
HOST: htznr2                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- _gateway                   0.0%  1000    6.6   4.8   2.4  22.9   1.5
  2.|-- 10114.your-cloud.host     84.4%  1000    0.3   0.3   0.2   1.4   0.1
  3.|-- ???                       100.0  1000    0.0   0.0   0.0   0.0   0.0
  4.|-- 85-10-250-153.clients.you  0.0%  1000    1.1   4.5   0.8  80.8  11.5
  5.|-- spine12.cloud1.nbg1.hetzn  0.0%  1000    1.2   4.8   0.8 159.2  12.4
  6.|-- 213-239-239-121.clients.y  0.0%  1000    0.7   2.0   0.4  47.6   4.1
  7.|-- core1.fra.hetzner.com      9.3%  1000    4.3   5.4   3.5  45.5   4.7
  8.|-- ae18.cr6-fra2.ip4.gtt.net  0.0%  1000    3.9   5.5   3.6  66.0   5.8
  9.|-- et-5-1-0.cr0-mil2.ip4.gtt  3.4%  1000   72.1  76.7  21.7 144.2  16.4
 10.|-- alpikom-gw.ip4.gtt.net     3.5%  1000   73.7  76.5  20.5 111.5  15.8
 11.|-- gw2-mi-te0100.mclink-net.  2.7%  1000   90.5  91.1  35.7 124.9  15.4
 12.|-- gw2-rm-gi0001.mclink-net.  3.6%  1000   79.6  86.1  37.7 121.9  15.2
 13.|-- 213.21.132.39              3.7%  1000   75.8  85.8  32.3 117.6  15.6
 14.|-- 213.21.132.69              3.0%  1000   78.4  87.7  30.9 330.5  20.2
 15.|-- 213.21.130.142             3.4%  1000   79.7  87.8  30.3 224.9  18.4
 16.|-- net77-43-16-001.mclink.it  5.0%  1000   93.7  91.9  36.4 210.8  18.4
lukas@htznr2:~$


Smokeping Host 77.43.16.1 (Irideos/ex MC Link):
https://smoke.ltri.eu/smokeping/smokeping.cgi?displaymode=n;start=2022-02-06%2003:32;end=now;target=External.GTT.AS5396IRIDEOShost

MTR storici:
2022-02-01T19:10
https://pastebin.com/raw/MSvuSuR0

2022-02-02T18:39
https://pastebin.com/raw/zWD8GHGa

2022-02-03T21:33
https://pastebin.com/raw/DHWDyi1g

2022-02-04T14:11
https://pastebin.com/raw/qhrWZBQX

2022-02-06T20:16 (come sopra durante congestione)
https://pastebin.com/raw/5bcsajmm

2022-02-07T00:30 (come sopra in assenza di congestione. qua tutto ok)
https://pastebin.com/raw/i8PE9PR8

2022-02-07T14:36 (come sopra con 3%PL)
https://pastebin.com/raw/bxhjQwbL


Un ticket è stato aperto verso GTT il 01/02.


cheers,
lukas


Maggiori informazioni sulla lista itnog