Web lists-archives.com

Re: Strange Network Problem






On 08/31/2018 10:41 PM, David Christensen wrote:
On 08/31/2018 12:50 PM, Stephen P. Molnar wrote:
I am running Debian Stretch on my Linux platform.

I have noticed low internet traffic when I have not been doing anything outside of my LAN. This has made me a tad suspicious.

Now:

root@AbNormal:/home/comp# ifconfig
enp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
inet 162.237.98.238 netmask 255.255.252.0 broadcast 162.237.99.255
         ether bc:ee:7b:5e:83:36  txqueuelen 1000  (Ethernet)
         RX packets 796401  bytes 529829454 (505.2 MiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 236054  bytes 22520861 (21.4 MiB)
         TX errors 0  dropped 0 overruns 0  carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
         inet 127.0.0.1  netmask 255.0.0.0
         loop  txqueuelen 1  (Local Loopback)
         RX packets 399  bytes 42360 (41.3 KiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 399  bytes 42360 (41.3 KiB)
         TX errors 0  dropped 0 overruns 0  carrier 0 collisions 0


It turns out that this ISP, 162.237.98.238 is my ISP, AT&T here in Columbus, Ohio.

The other four nodes on my LAn all have IP's starting with 192.168.1 - which is what it's supposed to be.

Just what is going on here? I don't have a clue.

I dop have firewalls implemented on both the modem and the computers.

Any insights will be much appreciated.

Thanks in advance.


Running nslookup(1):

    2018-08-31 18:53:21 dpchrist@vstretch ~
    $ nslookup 162.237.98.238
    Server:        192.168.5.1
    Address:    192.168.5.1#53

    Non-authoritative answer:
238.98.237.162.in-addr.arpa name = 162-237-98-238.lightspeed.clmboh.sbcglobal.net.

    Authoritative answers can be found from:


Running host(1):

    2018-08-31 18:58:15 dpchrist@vstretch ~
    $ host 162.237.98.238
238.98.237.162.in-addr.arpa domain name pointer 162-237-98-238.lightspeed.clmboh.sbcglobal.net.


162.237.98.238 appears to be a valid IPv4 public Internet address.


You should have a device provided by your Internet service provider (ISP) between their wiring (e.g. telephone service) and your wiring (e.g. Ethernet local area network/LAN). What is the make and model of the ISP device? Please provide a URL to the product support page.


What are the "other four nodes"?


How is everything interconnected?


David


Thanks for your reply.

ISO device is an Arris BGE210-700 Broadband Gateway Release 1.0 from AT&T (http://www.arris.com/Search/?q=Arris+BGE210-700+Broadband+Gateway)

Wired Connections:  2 Desktops,  printer and VOIP telephone

Wireless Connections:  Laptop and two Android Smartphones

root@AbNormal:/home/comp# nslookup
> nslookup -a
Server:        192.168.1.254
Address:    192.168.1.254#53

Non-authoritative answer:
Name:    nslookup
Address: 198.105.244.130
Name:    nslookup
Address: 104.239.207.44
>
> host
Server:        192.168.1.254
Address:    192.168.1.254#53

Non-authoritative answer:
*** Can't find host: No answer
>

--
Stephen P. Molnar, Ph.D.
Consultant
www.molecular-modeling.net
(614)312-7528 (c)
Skype: smolnar1