[ale] home network monitoring

[Alex Carver]

On 2015-12-11 06:21, Pete Hardie wrote:
> Good monring all,
> 
> I've had some sporadic issues in my home network, and I'd like to try and
> troubleshoot them, but need advice on
> how - is there an existing product that would do this?  Or am I better off
> writing something myself?
> 
> ​My setup is:
> cable modem in bridge mode -> ASUS wifi+wired router, with wifi and wired
> machines in the house, and some powerline networking for a few DVRs that
> are too old for wifi
> 
> 
> The issues:
> 1) sporadic loss of wifi connection - like my SSID is not visible for 10s
> of seconds, and
> 2) sporadic loss of connectivity to the Intarweb at large - nothing seems
> to get out/back for minutes at a time
> 
> ​
> ​What I would like to do is monitor connectivity from my (wired) desktop​
> to the fixed points in my internal network, and some strategic outside
> sites (Google DNS, Comcast DNS, wikipedia, or others with good
> uptime/connectivity), and generate a periodic report on when and for how
> long connectivity was lost to each.
> 
> ​Does anyone have recommendations?  Does systemd cover this yet? :)

Are you using stock firmware on the ASUS or open source (DD-WRT,
OpenWRT, etc.)?

Are you able to look at the diagnostic information on the cable modem
(such as routing tables, etc.)?

Ping monitoring to Google DNS and Comcast DNS would probably be
sufficient (no need to ping Wikipedia and burn their resources, Comcast
has more money :) )

I would also consider having your modem and router logs relayed to a
machine with an actual hard drive so you can review them.  (You just
need rsyslogd or syslog-ng to open a port and use filtering to dump the
logs to their own files.)

I would agree with Derek that it sounds like some of your hardware may
be misbehaving and monitoring that hardware directly would be beneficial.

By example, I have Uverse with static IPs but the modem performs
connection tracking through the NAT tables even on those (dumb but
true).  The state table is not very large so occasionally something like
a massive probe from the outside will fill the table and my external
connections drop.  Once the table entries expire away, everything comes
back.

I have OpenWRT on my router and use mrtg to monitor the traffic volume
while its system logs are sent to another machine running syslog-ng
where I can keep a window up running tail on that file.  The modem has
the same configuration for its logs but I can't run mrtg on it.