On the front panel of this machine, is the indicator light that tells me the HD is performing something. Normally, it is not that active. But all day today, I've noticed it running non-stop. I've done a re-start twice now, and it it is still going. It kinda worries me. I first thought I was getting updates installed, but there is nothing indicating what task it is doing. Does any one have any idea what this might be? This is the first time this has happened.
There are numerous programs to enable the user to see what is happening on the machine. A common one is htop in a terminal. One can open a terminal, preferably one which occupies a large part of the screen so all the output fits and can be viewed, and run:
htop.
The display will show, by default at the top of the screen, the activity of each cpu core, memory usage and total, and swap usage. In the columns under the titlebar, are shown the processes that are using the machine. It updates every few seconds so as processes come and go, they show up for the user who is viewing the output.
In particular, what may be of interest are the processes that are consuming memory and the cpu. With a mouse click on "CPU%" or "MEM%", the columns of either of those features will list what's using them, shown from greatest users down. The "Command" column shows the processes. For help with manipulating the output, press F1 to see the commands that alter htop itself.
Another program that provides similar information is
top. And a further one is
glances which has a different presentation of similar but also other information.
If the issue is networking, one can watch what's happening on the network with the programs:
vnstat, or as root,
iftop or
nethogs. There's some learning involved for using each of these programs to get the best out of them and understand the outputs. There are many other network monitors too. Linux has an abundance of such tools all with slightly difference nuances and with more or less information in the outputs.
To view what the machine is listening for, one can run:
ss -tulpen which shows the ports on the systems used for listening, for example if ssh service is listening for inputs. If the ssh daemon is running, one can check it in the htop output by clicking on the search function in htop at the bottom of the page, entering "ssh" and htop will show the stats for it by highlighting the relevant line. If nothing is currently connecting by ssh, then usually there is no cpu or memory usage.
