# Using ATT Fiber Home Network Accessing China Website Issue Debugging Info

## Debugging Info When I Cannot Access
### IPv4
`99.21.39.0`
### traceroute

$ traceroute www.douban.com
traceroute: Warning: www.douban.com has multiple addresses; using 49.233.242.15
traceroute to tc.forward.douban.com (49.233.242.15), 64 hops max, 52 byte packets
 1  dsldevice (192.168.1.254)  2.013 ms  1.709 ms  1.846 ms
 2  76-244-40-1.lightspeed.sntcca.sbcglobal.net (76.244.40.1)  2.914 ms  3.725 ms  5.901 ms
 3  71.148.149.96 (71.148.149.96)  3.761 ms  6.921 ms  5.013 ms
 4  cr2.sffca.ip.att.net (12.123.15.190)  11.589 ms  11.349 ms  7.075 ms
 5  12.122.114.5 (12.122.114.5)  9.882 ms  10.060 ms  7.605 ms
 6  192.205.32.34 (192.205.32.34)  7.940 ms  20.627 ms  30.809 ms
 7  * * *
 8  * * 202.97.85.53 (202.97.85.53)  150.580 ms
 9  * * *
10  * * *
11  36.110.249.74 (36.110.249.74)  198.668 ms * *
12  36.110.203.90 (36.110.203.90)  182.247 ms
    36.110.203.230 (36.110.203.230)  155.758 ms *
13  * * *
14  * * *
15  * * *
16  * * *
17  * * *
18  * * *
19  * * *
20  * * *
21  * * *
22  * * *
23  * * *
24  * * *
25  * * *
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *
31  * * *
32  * * *
33  * * *
34  * * *
35  * * *
36  * * *
37  * * *
38  * * *
39  * * *
40  * * *
41  * * *
42  * * *
43  * * *
44  * * *
45  * * *
46  * * *
47  * * *
48  * * *
49  * * *
50  * * *
51  * * *
52  * * *
53  * * *
54  * * *
55  * * *
56  * * *
57  * * *
58  * * *
59  * * *
60  * * *
61  * * *
62  * * *
63  * * *
64  * * *

### ping

$ ping www.douban.com
PING tc.forward.douban.com (49.233.242.15): 56 data bytes
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
Request timeout for icmp_seq 6
Request timeout for icmp_seq 7
Request timeout for icmp_seq 8
Request timeout for icmp_seq 9
64 bytes from 49.233.242.15: icmp_seq=10 ttl=49 time=159.432 ms
Request timeout for icmp_seq 11
Request timeout for icmp_seq 12
Request timeout for icmp_seq 13
Request timeout for icmp_seq 14
Request timeout for icmp_seq 15
Request timeout for icmp_seq 16
Request timeout for icmp_seq 17
Request timeout for icmp_seq 18
Request timeout for icmp_seq 19
Request timeout for icmp_seq 20
Request timeout for icmp_seq 21
Request timeout for icmp_seq 22
Request timeout for icmp_seq 23
Request timeout for icmp_seq 24
Request timeout for icmp_seq 25
Request timeout for icmp_seq 26
Request timeout for icmp_seq 27
Request timeout for icmp_seq 28
Request timeout for icmp_seq 29
Request timeout for icmp_seq 30
64 bytes from 49.233.242.15: icmp_seq=31 ttl=49 time=166.298 ms
Request timeout for icmp_seq 32
Request timeout for icmp_seq 33
Request timeout for icmp_seq 34
Request timeout for icmp_seq 35
Request timeout for icmp_seq 36
Request timeout for icmp_seq 37
Request timeout for icmp_seq 38
Request timeout for icmp_seq 39
Request timeout for icmp_seq 40
Request timeout for icmp_seq 41
Request timeout for icmp_seq 42
Request timeout for icmp_seq 43
Request timeout for icmp_seq 44
Request timeout for icmp_seq 45
Request timeout for icmp_seq 46
Request timeout for icmp_seq 47
Request timeout for icmp_seq 48
Request timeout for icmp_seq 49
Request timeout for icmp_seq 50
Request timeout for icmp_seq 51
64 bytes from 49.233.242.15: icmp_seq=52 ttl=49 time=171.488 ms
Request timeout for icmp_seq 53
Request timeout for icmp_seq 54
Request timeout for icmp_seq 55
Request timeout for icmp_seq 56
Request timeout for icmp_seq 57
Request timeout for icmp_seq 58
Request timeout for icmp_seq 59
Request timeout for icmp_seq 60
CRequest timeout for icmp_seq 61
Request timeout for icmp_seq 62
Request timeout for icmp_seq 63
Request timeout for icmp_seq 64

## Debugging Info When I Can Access
### IP Address

99.21.39.0

### Ping

ping www.douban.com
PING tc.forward.douban.com (81.70.124.99): 56 data bytes
64 bytes from 81.70.124.99: icmp_seq=0 ttl=50 time=153.379 ms
64 bytes from 81.70.124.99: icmp_seq=1 ttl=50 time=152.312 ms
64 bytes from 81.70.124.99: icmp_seq=2 ttl=50 time=151.765 ms
64 bytes from 81.70.124.99: icmp_seq=3 ttl=50 time=165.702 ms
64 bytes from 81.70.124.99: icmp_seq=4 ttl=50 time=184.146 ms
64 bytes from 81.70.124.99: icmp_seq=5 ttl=50 time=186.532 ms
Request timeout for icmp_seq 6
Request timeout for icmp_seq 7
Request timeout for icmp_seq 8
Request timeout for icmp_seq 9
Request timeout for icmp_seq 10
Request timeout for icmp_seq 11
Request timeout for icmp_seq 12
64 bytes from 81.70.124.99: icmp_seq=13 ttl=50 time=172.030 ms
64 bytes from 81.70.124.99: icmp_seq=14 ttl=50 time=160.534 ms
64 bytes from 81.70.124.99: icmp_seq=15 ttl=50 time=151.467 ms
64 bytes from 81.70.124.99: icmp_seq=16 ttl=50 time=156.559 ms
64 bytes from 81.70.124.99: icmp_seq=17 ttl=50 time=153.131 ms
64 bytes from 81.70.124.99: icmp_seq=18 ttl=50 time=154.670 ms
64 bytes from 81.70.124.99: icmp_seq=19 ttl=50 time=162.779 ms
64 bytes from 81.70.124.99: icmp_seq=20 ttl=50 time=190.221 ms
Request timeout for icmp_seq 21
Request timeout for icmp_seq 22
Request timeout for icmp_seq 23
Request timeout for icmp_seq 24
Request timeout for icmp_seq 25
64 bytes from 81.70.124.99: icmp_seq=26 ttl=50 time=178.032 ms
64 bytes from 81.70.124.99: icmp_seq=27 ttl=50 time=166.447 ms
64 bytes from 81.70.124.99: icmp_seq=28 ttl=50 time=150.152 ms
64 bytes from 81.70.124.99: icmp_seq=29 ttl=50 time=152.077 ms
64 bytes from 81.70.124.99: icmp_seq=30 ttl=50 time=150.402 ms
64 bytes from 81.70.124.99: icmp_seq=31 ttl=50 time=151.670 ms
64 bytes from 81.70.124.99: icmp_seq=32 ttl=50 time=151.432 ms
64 bytes from 81.70.124.99: icmp_seq=33 ttl=50 time=162.041 ms
64 bytes from 81.70.124.99: icmp_seq=34 ttl=50 time=181.754 ms
64 bytes from 81.70.124.99: icmp_seq=35 ttl=50 time=191.825 ms
Request timeout for icmp_seq 36
Request timeout for icmp_seq 37
Request timeout for icmp_seq 38
Request timeout for icmp_seq 39
Request timeout for icmp_seq 40
64 bytes from 81.70.124.99: icmp_seq=41 ttl=50 time=176.073 ms
64 bytes from 81.70.124.99: icmp_seq=42 ttl=50 time=162.309 ms
64 bytes from 81.70.124.99: icmp_seq=43 ttl=50 time=150.963 ms
64 bytes from 81.70.124.99: icmp_seq=44 ttl=50 time=157.401 ms
64 bytes from 81.70.124.99: icmp_seq=45 ttl=50 time=153.232 ms
64 bytes from 81.70.124.99: icmp_seq=46 ttl=50 time=161.745 ms
64 bytes from 81.70.124.99: icmp_seq=47 ttl=50 time=173.576 ms
64 bytes from 81.70.124.99: icmp_seq=48 ttl=50 time=203.504 ms
Request timeout for icmp_seq 49
Request timeout for icmp_seq 50
Request timeout for icmp_seq 51
Request timeout for icmp_seq 52
Request timeout for icmp_seq 53
Request timeout for icmp_seq 54
Request timeout for icmp_seq 55
64 bytes from 81.70.124.99: icmp_seq=56 ttl=50 time=172.651 ms
^C
--- tc.forward.douban.com ping statistics ---
57 packets transmitted, 33 packets received, 42.1% packet loss
round-trip min/avg/max/stddev = 150.152/164.925/203.504/14.361 ms

### mtr output (Traceroute doesn't work)

Start: 2022-04-26T15:32:04-0700
HOST:       Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.1.254              0.0%    10    2.2   3.3   1.8   7.4   1.6
  2.|-- 76-244-40-1.lightspeed.sn  0.0%    10    5.2   7.1   5.2  11.9   2.1
  3.|-- 71.148.149.96              0.0%    10    6.7   6.9   4.4  11.1   1.8
  4.|-- cr2.sffca.ip.att.net (12.  0.0%    10    9.6  12.7   7.9  15.7   3.1
  5.|-- 12.122.114.5               0.0%    10    7.6  10.4   6.9  21.4   4.2
  6.|-- 192.205.32.34             30.0%    10   34.4  21.6  10.1  40.0  11.3
  7.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
  8.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
  9.|-- 202.97.83.34              90.0%    10  179.9 179.9 179.9 179.9   0.0
 10.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
 11.|-- 101.95.247.118            70.0%    10  212.8 214.3 209.2 220.7   5.9
 12.|-- 101.226.210.74            60.0%    10  172.8 177.5 171.2 194.0  11.0
 13.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
 14.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
 15.|-- ???                       100.0    10    0.0   0.0   0.0   0.0   0.0
 16.|-- 140.143.177.206           40.0%    10  206.3 205.2 194.6 217.9  10.6