Fastmail completely inaccessible from Airtel 4G since last few days

[ishanjain28]

Hey,
Is fastmail.com's web interface, SMTP, IMAP working for anyone here on Airtel 4G?

Ping to fastmail.com's addresses shows 100% packet loss. SMTP/IMAP and other services are also not working.

I initially thought that maybe there is something weird in my setup but I can't reach fastmail.com on my phone(using Airtel 4G).

There aren't any probes in AS45609 to test it that way.

 

[ishanjain28]

mtr,

Starts of with,

                                                My traceroute  [v0.94]
emerald (10.0.10.5) -> fastmail.com                                                           2022-01-30T22:13:10+0530
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                                                              Packets               Pings
 Host                                                                       Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. _gateway                                                                 0.0%     4    1.7   1.7   1.6   1.8   0.1
 2. 192.168.8.1                                                              0.0%     4    0.6   0.5   0.5   0.6   0.0
 3. 10.206.17.17                                                             0.0%     4   72.4  91.8  32.1 168.6  57.3
 4. (waiting for reply)
 5. 10.206.248.153                                                           0.0%     4   53.6 105.9  53.6 162.5  46.1
 6. 125.16.168.237                                                           0.0%     4   85.9  83.6  38.9 112.5  31.7
 7. 116.119.52.165                                                           0.0%     4  313.8 308.2 256.3 354.6  49.4
 8. (waiting for reply)

Finally changes to,

                                                My traceroute  [v0.94]
emerald (10.0.10.5) -> fastmail.com                                                           2022-01-30T22:12:39+0530
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                                                              Packets               Pings
 Host                                                                       Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. _gateway                                                                 0.0%    23    1.7   1.5   1.0   1.7   0.2
 2. 192.168.8.1                                                              0.0%    23    0.6   0.7   0.4   1.3   0.2
 3. 10.206.17.17                                                             0.0%    23   59.8  64.3  24.2 121.6  25.5
 4. (no route to host)

 

[ishanjain28]

Adding some more data.

My Phone's public IPv4 address is, 106.211.x.y and fastmail is inaccessible from this.

I shutdown the lte modem for a few minutes and started it back up. Now, the lte modem has 117.99.29.x IP and fastmail is accessible from that IP block.

Fastmail doesn't have AAAA records so can't test that.

 

[wheatbread]

First hop 70 ms away, damn. Are you on 3G?

ee (100.65.230.23) -> imap.fastmail.com                                              2022-01-30T17:54:37+0000
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                                                        Packets               Pings
 Host                                                                 Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. 192.168.27.237                                                     0.0%    30   52.1  87.8  31.7 252.2  72.7
 2. 192.168.27.137                                                     0.0%    30   46.4  40.0  20.8  70.3  10.1
 3. 192.168.31.226                                                     3.3%    30   59.2  39.2  23.6  59.2   9.5
 4. 192.168.31.237                                                     0.0%    30   28.0  35.1  22.0  58.1   9.6
 5. 182.78.194.61                                                      0.0%    30   34.7  41.9  24.5  60.2   8.8
 6. aes-static-150.36.144.59.airtel.in                                 0.0%    30  292.1 283.1 261.2 301.8   8.7
 7. nyiix.10ge.nyc.bboi.net                                            0.0%    29  309.6 323.3 304.2 334.0   8.0
 8. 66.216.2.132                                                       0.0%    29  307.3 309.7 299.0 326.2   7.3
 9. 66.216.2.167                                                       0.0%    29  319.6 317.7 304.1 333.4   6.1
10. 64.135.10.100                                                      0.0%    29  324.4 308.8 295.8 324.4   6.4
11. imap.fastmail.com                                                  0.0%    29  302.0 307.2 294.4 331.9   9.4

 

[ishanjain28]

I am on 4G.

It's a bit better after I got the 117.99.29.x IP.

                                                My traceroute  [v0.94]
emerald (10.0.10.5) -> imap.fastmail.com                                                      2022-01-30T23:40:01+0530
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                                                              Packets               Pings
 Host                                                                       Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. _gateway                                                                 0.0%    12    0.3   0.3   0.2   0.3   0.0
 2. 192.168.8.1                                                              0.0%    12    0.4   0.4   0.4   0.6   0.1
 3. 106.208.188.193                                                          0.0%    12   39.2  43.3  16.7  62.5  16.1
 4. 117.96.31.31                                                             0.0%    12   27.7  37.5  17.1  51.4   9.6
 5. 182.79.109.85                                                            0.0%    12   57.0  46.3  26.0  86.9  18.3
 6. 116.119.52.165                                                           0.0%    12  269.0 267.8 245.0 287.4  15.0
 7. nyiix.10ge.nyc.bboi.net                                                  0.0%    12  300.8 310.7 284.2 323.5  11.2
 8. 66.216.2.132                                                             0.0%    12  295.9 300.7 290.3 310.9   6.2
 9. 66.216.2.167                                                             0.0%    12  316.8 298.2 281.5 319.2  13.6
10. 64.135.10.100                                                            0.0%    12  313.6 304.8 279.8 322.1  15.3
11. imap.fastmail.com                                                        0.0%    11  293.5 305.5 293.5 318.7   8.1

 

[pothi]

While I don't use fastmail, I can't ping it either. I came here (to the forum) because my clients' sites aren't accessible from two different Airtel 4G connections. Simplenote stopped syncing too. Fortunately, I had a VPS that got wireguard VPN. So, enabled peers for my mobile and desktop to get everything going, on a Monday. Didn't check the last weekend. So, this partial blocking may have started earlier.

 

---

[phoenix10386]

Is this occurring only on Airtel ?

 

[pothi]

Yet to check with other ISPs. Since Airtel is the most reliable for data in this area, I use only Airtel (with a backup connection).

 

[mikrotik]

Tracing route to fastmail.com [66.111.4.147]
over a maximum of 30 hops:

1 3 ms 2 ms 61 ms 192.168.0.1
2 57 ms 4 ms 3 ms abts-north-dynamic-255.47.161.122.airtelbroadband.in [122.161.47.255]
3 55 ms 3 ms 3 ms 125.21.160.21
4 220 ms 220 ms 269 ms 116.119.52.163
5 354 ms 306 ms 306 ms nyiix.10ge.nyc.bboi.net [198.32.160.137]
6 298 ms 305 ms 306 ms 66.216.2.132
7 280 ms 307 ms 306 ms 66.216.2.167
8 312 ms 306 ms 307 ms 64.135.10.100
9 310 ms 305 ms 306 ms www.fastmail.com [66.111.4.147]

Trace complete.

Reachable here on Airtel Fiber.

 

[ishanjain28]

Is this occurring only on Airtel ?

so far I have only seen this on Airtel 4G that have that 106.x.y.z public IP address. It's reachable from all the probes, Atlas Console