Hi

I have a VPS from servint, and lately I have noticed a large increase in connection errors

Some questions
1/ How can I monitor this server remotely to ascertain its performance. I am aware you can buy rather high priced services for this but is there another way?

2/ How can I determine if I am under some sort of DDOS attack?

3/ are there other causes I should look for? (no changes have been made to the server except nightly cpanel updates)


Any help greatly appreciated

Originally posted by Managedlinks
Hi

I have a VPS from servint, and lately I have noticed a large increase in connection errors

Some questions
1/ How can I monitor this server remotely to ascertain its performance. I am aware you can buy rather high priced services for this but is there another way?

2/ How can I determine if I am under some sort of DDOS attack?

3/ are there other causes I should look for? (no changes have been made to the server except nightly cpanel updates)


Any help greatly appreciated

First, I am not certain what you mean when you say connection errors or what exactly is failing/causing problems and where you are seeing these errors. Post more detail about what you mean when you say connection errors, and I'm sure more folks can help out.

Second, I would check your UBCs (user bean counters) and look for any failures there:

cat /proc/user_beancounters

And look for the values in the "failcnt" column, and post the results if any have failcnt values, with the other info listed above. This will make a good starting point.

Ok sorry for the vagueness

Connection errors...
DNS errors, I host my own nameservers.
Transmission errors, a file will be in the process of being downloaded and the connection will drop for no apparent reason
it seems to simply close. it can be picked up again but may be repeatedly dropped for a largish file > 3 Megs

These are problems I have noticed, I have not had any complaints, BUT most people don't complain they simply move on. and I have had a huge drop off in custom > 50% in the last few weeks.

So without anything else to go on (everything else seems static) I thought the problem may be server related.

I am unaware of what UBC's are but the file "/proc/user_beancounters" has no entries (0 bytes long)

Does this mean its disabled ? if so how do I enable it?

Thanks for the help so far.

Originally posted by Managedlinks
Ok sorry for the vagueness

Connection errors...
DNS errors, I host my own nameservers.
Transmission errors, a file will be in the process of being downloaded and the connection will drop for no apparent reason
it seems to simply close. it can be picked up again but may be repeatedly dropped for a largish file > 3 Megs

These are problems I have noticed, I have not had any complaints, BUT most people don't complain they simply move on. and I have had a huge drop off in custom > 50% in the last few weeks.

So without anything else to go on (everything else seems static) I thought the problem may be server related.

I am unaware of what UBC's are but the file "/proc/user_beancounters" has no entries (0 bytes long)

Does this mean its disabled ? if so how do I enable it?

Thanks for the help so far.

You MUST have this file, if you are running a VPS, make sure you are root and type:

bash-2.05b# cat /proc/user_beancounters

You can also see these parameters logging into your VZPP on 2.6 based VPS', and see graphically if you are hitting limits, resources, etc if you cannot find them from the cli.

Are you uploading via the web? Perhaps an upload file size limit in php.ini? Are you running any panels (plesk, cpanel, etc)?

How are you tracking connection errors on DNS that point you to a communications problem?

Originally posted by TomK
You MUST have this file, if you are running a VPS, make sure you are root and type:


As I said the file is there, it is simply 0 bytes long so I assumed that meant the service wasn't running

When I do a 'cat' as you suggested I do get a list of details
In all cases the failcnt column is zero


Re: DNS
I have had a customer send me Download manager log which showed multiple DNS lookup failures.

I also get reports from InternetSEER which reported DNS problems, they also report average connection time (how long it takes to connect) as being ~10 seconds which seems very high to me

I have assumed the above were network related not server related as they seemed to be intermittant

So I have no scientific data just the above, thats why I want to take a more scientific approach

the VPS is Virtuozzo
it uses CPanel (updated nightly)

Email our NOC, they'll do a full investigation of your problem and work with you to find a solution. You can also contact me directly and I'll ensure you get the assistance you require.

Hi Bob

I was going to email NOC but I wasnt sure and still aren't sure the problem is in the server.

I really didn't want to hassle the NOC if the problem is elsewhere (like in my head, I always panic when income dips), and it would really be good for me to have a way of monitoring the service anyway. no offence intended, its just I am being slack by not doing it.

Thanks for the response and the NOC is always super responsive and helpfull