Frank's Blog

Let’s think about monitoring, linux server monitoring to be precisely. As long as a server is working fine, responds fast and there are enough ressources free everything is okay. But it these times of crisis, saving money and so one, maybe the system administrator is forced to put more services within the same hardware to use mostly all ressources, to push the server to the limits.

But, what are the limits ?

Of course, on linux there is the famous load, showing a mix of several ingredientes like cpu and memory usage, harddisc activity, or something like this.

But what do you do when the load climbs up to 10 or 20 ?
Are these values critical or not ?
How do you find the problem or bottleneck ?

Lately I stumbled about these questions during a migration of a web service and I asked the all-knowing trash heap (aka google) about it. Maybe I didn’t ask correctly or we didn’t understand each other, anyway, the result wasn’t that satisfying because I didn’t find any dedicated tool to have all relevent data of a operating system on sight.
Instead I found some nice articles how to use commands like vmstat, mpstat, free, etc.
Of course, these commands are quite useful and do their job perfectly, but I don’t want to open up 5 to 10 terminals, connect via secure shell to the server in question and fire up one command in every session, maybe inside a “while true; do something; sleep 2; done” loop. That’s not comfortable at all.
I was searching for kindda “show_me_all_data_I_want” thing, giving me an overview about “all” (to me) relevent data inside one session window, refreshing ever 1, 2 or 5 seconds.

This leeds to the question: what are “all” (to me) relevent data ?

In my actual case, a web server with apache2, mysql, php5 and some wordpress instances, I would like to see load, cpu and memory usage overall, cpu and memory usage of apache and mysql as the main workers, count of apache and mysql processes, count of current network connections on port 80 and maybe other usefull things a don’t know right know.
Oh, by the way, this tool shouldn’t use lots of ressources so the shown data will be reliable.

Seems, like I have a new project!
Now I have to find a name for it, choose a programming language and start!

Googling some obvious word combinations like serverview, or whatsup showed me what to take not.

So I chose HowAreU !

Maybe I should add a “Now” to point the realtime character more out ?
What do you think ?