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A comment on Twitter experiencing outages. Parent comment

Re:Twitter experiencing outages by xiaodown on Monday November 07, 2016 @01:17AM (#12889221)
Yep, i'm no expert, but a BGP looking glass seems to suggest that all of the best paths (chosen by AS pathlength?) are not being advertised to peers... But some routes are being advertised? Idk

    Router: Palo Alto, CA - US
    Command: show ip bgp 104.244.42.193

    BGP routing table entry for 104.244.42.0/24
    Versions:
    Process           bRIB/RIB  SendTblVer
    Speaker          261897778   261897778
    Last Modified: Nov  7 06:11:36.675 for 00:02:37
    Paths: (4 available, best #3)
    Advertised to update-groups (with more than one peer):
    0.2 0.3 0.6 0.7
    Advertised to peers (in unique update groups):
    129.250.47.126  129.250.9.146   128.242.180.62  80.150.168.193
    128.241.2.58

    Path #1: Received by speaker 0
    Not advertised to any peer
    13414 13414
    116.51.31.10 (metric 14530) from 129.250.0.18 (129.250.0.18)
    Origin IGP, localpref 120, valid, confed-internal
    Received Path ID 0, Local Path ID 0, version 0
    Community: 2914:370 2914:1405 2914:2406 2914:3400 65400:4134 65420:4134 65460:4134

    Path #2: Received by speaker 0
    Not advertised to any peer
    13414 13414
    62.73.183.110 (metric 28640) from 129.250.0.30 (129.250.0.30)
    Origin IGP, localpref 120, valid, confed-internal
    Received Path ID 0, Local Path ID 0, version 0
    Community: 2914:370 2914:1204 2914:2205 2914:3200 65400:4134 65420:4134 65460:4134

    Path #3: Received by speaker 0
    Advertised to update-groups (with more than one peer):
    0.2 0.3 0.6 0.7
    Advertised to peers (in unique update groups):
    129.250.47.126  129.250.9.146   128.242.180.62  80.150.168.193
    128.241.2.58
    13414 13414
    129.250.195.210 (metric 7029) from 129.250.0.115 (129.250.0.167)
    Origin IGP, localpref 120, valid, confed-internal, best, group-best
    Received Path ID 0, Local Path ID 1, version 261897778
    Community: 2914:370 2914:1007 2914:2000 2914:3000 65400:4134 65420:4134 65460:4134
    Originator: 129.250.0.167, Cluster list: 0.0.0.6

    Path #4: Received by speaker 0
    Not advertised to any peer
    13414 13414
    129.250.195.210 (metric 7029) from 129.250.0.116 (129.250.0.167)
    Origin IGP, localpref 120, valid, confed-internal
    Received Path ID 0, Local Path ID 0, version 0
    Community: 2914:370 2914:1007 2914:2000 2914:3000 65400:4134 65420:4134 65460:4134
    Originator: 129.250.0.167, Cluster list: 0.0.0.6
edit: sorry about formatting, i've tried to clean it up.
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Re:Twitter experiencing outages by mmaunder on Monday November 07, 2016 @01:30AM (#12889298)
Updates from outages list:

Update 1:

Looks like their networks are not announced anymore. From 4 providers, we don't see any network matching 104.244.42.1, 104.244.42.65, 104.244.42.129 or 104.244.42.193 (A records for twitter.com)

Update 2:

show ip bgp 104.244.42.0/24 % Network not in table No routes present...

Update 3: (3 mins ago)

Networks are back now, but quite some packet loss. Also, Comcast in norcal goes via Level3 to Twitter in London. They are also announcing direct to NTT which seems to get served locally. So, they're not quite out of the woods yet.

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Re:Twitter experiencing outages by mfincham on Monday November 07, 2016 @01:25AM (#12889270)
You can ignore things like "Not advertised to any peer" in looking glass output, just a function of a router being used as the looking glass server and not participating in routing.
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