On 6/13/22 4:30 AM, George N. White III wrote:
You will find it well worth the effort to learn some basics of
network
troubleshooting:
A beginner's guide to network troubleshooting in Linux | Enable Sysadmin
(
redhat.com)
<
https://www.redhat.com/sysadmin/beginners-guide-network-troubleshooting-l...
I gave it a first pass. For me, it seemed to be overkill; much was over
my head. But I'll give it a second-pass reading later.
The only speed test I've ever seen seemed very
"snoopy" and intrusive
the last time I accessed it. That was some time ago, I don't recall
when. I do recall Firefox and/or NoScript not liking the site. I've
never seen any hint of a speed test being offered by my ISP
(comcast/xfinity), though I log into that company's site at least once
per month. Status site for comcast: see my reply to Tim. What if I
can't access comcast's/xfinity's site?
"Speed tests" are a popular way bad actors get victims to
sites that try
to extract money. Using your ISP's test should be as safe as anything
from your ISP. ShieldsUP!
https://www.grc.com/ <
https://www.grc.com/>
is a reputable site that
you can use to scan your system for internet accessible ports.
Tried that this morning, from Firefox running in Fedora. It seemed to
think it was a windows box that I was testing. Otherwise, the tests
seemed to work, and claimed my workstation was clean.
I could not access downdetector Saturday morning.
That is what I see when I'm having problems, but once service is
restored I can usually see the spike in reports around the time I had
a problem, which means I don't pester admins at the remote site I
couldn't reach.
I looked at that this morning to see if it would report on
comcast/xfinity. It did. Would have been nice if it had given me a way
of seeing back to Saturday morning, but I did not see any such
functionality.
Compare "ss -tl" results before, during, and after a zoom
session.
I'll try to remember to try that.
I'm using a wired connection only.
No wifi.
No router.
Are you running internet facing services (web page, ssh, etc.)? To list
active tcp connections and listening ports, use "ss -tl".
"ShieldsUp!!":
https://www.grc.com/ <
https://www.grc.com/> is a
reputable site that will tell you
which ports are open to the internet.
This is a "simple" home workstation: tower connected via 1 yellow
ethernet cable to one internet&voice modem. The phone is a land line.
I'm not running any internet-facing services that I know of. GRC says I
have no ports open to the internet, but it also seems to think this is a
windows box. (It is a Fedora and windows-7 dual boot system, but I was
using Fedora for the GRC tests.)
Thank-you, George.