network mystery!!??

[Jack Craig]

i have a networking mystery ; i hope someone might give me a clue.

i am working to restore a web server to internet access that is failing
after att update
the att older modem (pace 5238ac) with arris BGW210-700.

i have a static ip from att in the range 108.220.213.0/255.255.255.248,
108.220.213.121 is the external ip for the server.

the bgw210-700 is the primary router/modem and is connected to a 3rd party
router, netgear nighthawk,

the internal 10.0.0.0/  connects to the netgear nighthawk

ATT's broadband configuration is

 Blackhole-ATT (wireless name)

   Broadband connection source      DSL
   Broadband connection             up
   Broadband network type           lightspeed
   Broadband ipv4 address           108.90.204.76
   Broadband gateway address        108.90.204.1


outbound packets from the server (WS), are routed from the 10.0.0.1
nighthawk to the ATT router to the internet.

the 108.90.204.0 network routing from the att router to the att's gateway.
.76 is the router, .1 is the GW.

sample route, ...

10.0.0.101            ws.linuxlighthouse.com (internal IP) 2 packets
transmitted, 2 received, 0% packet loss, time 1033ms
10.0.0.1                           Blackhole-NH                         2
packets transmitted, 2 received, 0% packet loss, time 1018ms
192.168.1.254                 Blackhole-ATT                        2
packets transmitted, 2 received, 0% packet loss, time 1001ms
108.90.204.76             att subnet (local router)            2 packets
transmitted, 2 received, 0% packet loss, time 1002ms
108.90.204.1            att subnet (remote GW)               2 packets
transmitted, 2 received, 0% packet loss, time 1001ms
108.220.213.121   ws.linuxlighthouse.com (public IP) 2 packets transmitted,
2 received, 0% packet loss, time 1001ms
108.220.213.126   linuxlighthouse (public GW)          2 packets
transmitted, 2 received, 0% packet loss, time 1001ms

now the  mystery. where 108.220.213.121 is a publicly visible ip for the
server, a remote traceroute is wonky!!

consider the below traceroute, it reports hops up to 108.90.204.76,
stopping there instead of doing one more hop


  1    <1 ms    <1 ms    <1 ms  Linksys35675 [192.168.1.1]
  2     9 ms     8 ms    17 ms  142-254-236-209.inf.spectrum.com
[142.254.236.209]
  3    12 ms    10 ms    11 ms  lag-63.tjngcaac01h.netops.charter.com
[24.30.172.49]
  4    14 ms    13 ms    13 ms  lag-29.lsaicaev01r.netops.charter.com
[72.129.18.240]
  5    12 ms    14 ms    11 ms  lag-26.lsancarc01r.netops.charter.com
[72.129.17.0]
  6    19 ms    13 ms    14 ms  lag-16.lsancarc0yw-bcr00.netops.charter.com
[66.109.6.102]
  7    25 ms    37 ms    42 ms  lag-3.pr2.lax10.netops.charter.com
[107.14.19.41]
  8    17 ms    17 ms    17 ms  192.205.32.253
  9    22 ms    21 ms    21 ms  cr1.la2ca.ip.att.net [12.122.128.102]
 10    24 ms    25 ms    25 ms  12.122.158.41
 11     *        *        *     Request timed out.
 12     *        *        *     Request timed out.
 13    23 ms    21 ms    23 ms  99.134.39.15
 14    25 ms    24 ms    26 ms  99.161.44.79
 15    44 ms    43 ms    43 ms
108-90-204-76.lightspeed.mtryca.sbcglobal.net [108.90.204.76]
 16     *        *        *     Request timed out.
 17     *        *        *     Request timed out.
 18     *        *        *     Request timed out.
 19


could anyone shed some light on this mystery??

tia,jackc...