I think it would be nice if you show us or you compared just some network diagnostic results. I mean ping,
traceroute by ip and by name with VPN connection and without VPN connection.
It is normal procedure in such cases.
edited: fixed errors
You should post a traceroute both with your VPN and your ISP. This will most likely yield much more useful information and will give much more conclusive results as to if it is the anti-DDoS service or an issue with your VPN
It is an expected result to have timeout errors when attempting to ping the forum's IP address when you are unable to access it
edit:
I don't think the anti-DDoS service likes people to tracert the forum:
No VPN
Traceroute has started…
traceroute to bitcointalk.org (186.2.165.183), 64 hops max, 72 byte packets
-snip-
4 12.83.102.141 (12.83.102.141) 35.372 ms 50.019 ms 32.040 ms
5 12.122.154.162 (12.122.154.162) 42.939 ms 37.711 ms 36.510 ms
6 cr2.attga.ip.att.net (12.122.30.82) 39.248 ms 62.900 ms 35.360 ms
7 12.122.117.121 (12.122.117.121) 35.387 ms 41.532 ms 39.527 ms
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 ddos-guard.net (186.2.165.2) 127.142 ms 124.530 ms 131.947 ms
15 node-186-2-165-183.reverse.x4b.me (186.2.165.183) 128.055 ms 135.663 ms 133.614 ms
Traceroute has started…
traceroute to 186.2.165.183 (186.2.165.183), 64 hops max, 72 byte packets
-snip-
4 12.83.102.141 (12.83.102.141) 34.494 ms 57.647 ms 40.879 ms
5 12.122.154.162 (12.122.154.162) 35.817 ms 37.463 ms 53.991 ms
6 cr2.attga.ip.att.net (12.122.30.82) 35.148 ms 39.349 ms 35.061 ms
7 12.122.117.121 (12.122.117.121) 33.530 ms * 36.226 ms
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 ddos-guard.net (186.2.165.2) 180.387 ms 133.011 ms 150.389 ms
15 node-186-2-165-183.reverse.x4b.me (186.2.165.183) 124.622 ms 144.493 ms 180.666 ms
Behind PIA - east cost gateway:
Traceroute has started…
traceroute to bitcointalk.org (186.2.165.183), 64 hops max, 72 byte packets
1 * 10.168.1.1 (10.168.1.1) 54.869 ms 47.485 ms
2 108.61.68.129 (108.61.68.129) 60.919 ms 48.574 ms 51.532 ms
3 108.61.244.121 (108.61.244.121) 71.301 ms 56.625 ms 56.273 ms
4 ae-33.r05.nycmny01.us.bb.gin.ntt.net (128.241.2.201) 55.582 ms * 55.975 ms
5 ae-3.r06.nycmny01.us.bb.gin.ntt.net (129.250.4.205) 138.774 ms 65.133 ms 73.385 ms
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 ddos-guard.net (186.2.165.2) 133.579 ms 127.574 ms 142.507 ms
13 node-186-2-165-183.reverse.x4b.me (186.2.165.183) 134.889 ms 154.506 ms 129.043 ms
Behind Australia Melbourne gateway:
Traceroute has started…
traceroute to bitcointalk.org (186.2.165.183), 64 hops max, 72 byte packets
1 10.186.1.1 (10.186.1.1) 390.808 ms * 388.547 ms
2 168.1.75.3-static.reverse.softlayer.com (168.1.75.3) 398.475 ms 390.183 ms 416.742 ms
3 ae12.dar02.mel01.networklayer.com (168.1.118.136) 392.790 ms 405.587 ms 405.534 ms
4 ae9.bbr02.nd01.mel02.networklayer.com (50.97.19.78) 393.577 ms 403.574 ms *
5 * ae0.bbr02.eq01.syd02.networklayer.com (50.97.19.64) 467.495 ms 408.484 ms
6 * ae7.bbr01.eq01.syd02.networklayer.com (50.97.19.60) 406.300 ms 410.425 ms
7 ae1.bbr02.eq01.tok01.networklayer.com (50.97.19.67) 530.237 ms * *
8 ae0.bbr01.pn01.hkg01.networklayer.com (50.97.18.167) 572.426 ms 765.608 ms 618.066 ms
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 ddos-guard.net (186.2.165.2) 740.038 ms 919.166 ms 827.251 ms
16 node-186-2-165-183.reverse.x4b.me (186.2.165.183) 761.813 ms 752.532 ms 745.658 ms
From UK London gateway:
Traceroute has started…
traceroute to bitcointalk.org (186.2.165.183), 64 hops max, 72 byte packets
1 192.168.1.254 (192.168.1.254) 11.116 ms 30.467 ms 1.908 ms
2 99-114-148-3.lightspeed.chrlnc.sbcglobal.net (99.114.148.3) 33.108 ms 51.563 ms 30.862 ms
3 * 99.133.205.76 (99.133.205.76) 24.339 ms *
4 12.83.102.141 (12.83.102.141) 33.268 ms 27.656 ms 26.188 ms
5 12.122.154.162 (12.122.154.162) 36.318 ms 32.487 ms 67.926 ms
6 cr2.attga.ip.att.net (12.122.30.82) 63.113 ms 36.141 ms 34.724 ms
7 12.122.117.121 (12.122.117.121) 47.777 ms 42.252 ms 35.117 ms
8 * * *
9 * ae-2-6.ear1.amsterdam1.level3.net (4.69.153.190) 144.831 ms *
10 * * *
11 *traceroute: sendto: No route to host
traceroute: wrote bitcointalk.org 72 chars, ret=-1
*traceroute: sendto: No route to host
traceroute: wrote bitcointalk.org 72 chars, ret=-1
*
traceroute: sendto: No route to host
12 traceroute: wrote bitcointalk.org 72 chars, ret=-1
*traceroute: sendto: No route to host
Second try from UK London gateway
Traceroute has started…
traceroute to bitcointalk.org (186.2.165.183), 64 hops max, 72 byte packets
1 10.164.1.1 (10.164.1.1) 144.508 ms * 145.007 ms
2 2e1c3502.lon.100tb.com (46.28.53.2) 143.389 ms 139.378 ms 153.804 ms
3 * 83.170.70.225 (83.170.70.225) 147.705 ms 156.591 ms
4 linx-224.retn.net (195.66.224.193) 143.552 ms 147.772 ms 139.202 ms
5 et510-1.rt.m9.msk.ru.retn.net (87.245.232.2) 195.842 ms 189.148 ms 188.549 ms
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * ddos-guard.net (186.2.165.2) 209.088 ms
12 * node-186-2-165-183.reverse.x4b.me (186.2.165.183) 211.918 ms *
From UK London gateway to ghash.io (recent victim of strong DDoS attack)
Traceroute has started…
traceroute: Warning: ghash.io has multiple addresses; using 198.41.187.247
traceroute to ghash.io (198.41.187.247), 64 hops max, 72 byte packets
1 * 10.164.1.1 (10.164.1.1) 311.789 ms 377.274 ms
2 2e1c3503.lon.100tb.com (46.28.53.3) 133.720 ms 320.980 ms *
3 83.170.70.237 (83.170.70.237) 147.431 ms 155.485 ms 154.361 ms
4 linx-juniper.as13335.net (195.66.225.179) 149.369 ms 178.439 ms 199.921 ms
5 198.41.187.247 (198.41.187.247) 151.358 ms 163.211 ms 155.210 ms