andreszs's questions

I have a160 GB VPS with pre-installed CentOS 7 and Webuzo. Using the du -sh command in the www dir I noticed that my sites consume barely 60GB, while the total used space is 120 GB.

Which means my CentOS installation is using 60 GB of space. I read somewhere that 20 GB is enough to install CentOS, so the question is exactly how do I find out what's eating up all space? The Webuzo dir itself in /usr/ is less than 1 GB.

Being a Windows user, I'm not very fond of Unix commands, so any help will be appreciated... I need to free up as much space as possible, thanks. I have full root access via SSH and WinSCP.

To verify my domain, someone at Google requested me to create a CNAME with this:

Create the following CNAME record through your domain hosting provider:

Label/Host: deleteGAPPSnotBefore20171127utc

Destination/Target: case-XXXXX-for-example.com-at.google.com

Time to live (TTL): 3600

After creating it, I got this reply:

Unfortunately, we won´t be able to proceed with the process with the record reflecting as an alias. Please coordinate with your domain host and ask assistance in adding the provided record values as a CNAME record.

As much as I would love to accept the record you created as a proof of your domain ownership, our security policy requires us that the values be reflected in the proper record type.

Now, the definition itself says that CNAME is a type of record used to specify that a domain name is an alias for another domain.

The question is, what are these people from Google expecting me to do? How do I create a non-alias CNAME if a CNAME record is an alias by definition? There's no drop down box to select the CNAME type in Coudflare (and I guess in any other DNS panel for the matter).

This makes no sense, but I can't reply this to the Google support guy as they'll always stand their ground.

My server is being flooded until apache becomes non-responsive, and I need some help finding and blocking the responsible IP address(es).

Normally, I don't have more than 150 connections. Now I have thousands:

netstat -nat | awk '{print $6}' | sort | uniq -c | sort -n
      1 established)
      1 Foreign
     13 LAST_ACK
     20 CLOSING
     30 SYN_RECV
     41 LISTEN
     44 FIN_WAIT1
     74 FIN_WAIT2
     77 CLOSE_WAIT
    273 ESTABLISHED
   1960 TIME_WAIT

MRTG graph clearly shows the normal connections until the attack begins:

This is the result of counting connections per IP (end of list only):

netstat -atun | awk '{print $5}' | cut -d: -f1 | sed -e '/^$/d' |sort | uniq -c | sort -n
  5 4.59.90.216
  5 4.59.90.222
  5 4.59.90.237
  5 4.59.90.242
  5 74.125.26.95
  6 186.158.143.202
  6 216.58.219.162
  6 4.59.90.251
  7 104.24.5.60
  7 216.58.192.66
  7 4.59.90.212
  7 4.59.90.231
  7 4.59.90.241
  9 216.58.192.98
 10 189.177.214.89
 10 23.10.101.162
 11 4.59.90.226
 12 85.94.197.200
 25 216.58.219.66
 31 216.58.219.130
 40 0.0.0.0
 86 83.101.136.42
1026 10.0.0.2

The last one is the server's IP, I have not idea why it's shown. Thanks.

I'm using the following command to move all files (non-recursively) ended in _128.jpg into the 128x160 subdir. This works great.

find . -iname '*_128.jpg' | xargs -I '{}' mv {} 128x160

But I also need to remove the _128 suffix from each file. Also, I must keep my current xargs method, making an exec for each would make the process extremely longer.

Thanks in advance for your cooperation!

I have a few dedicated servers and for some reason they are totally unable to mantain the time properly synchronized, every few days they start having differences of minutes in the clock. So I have to manually open Putty, connect, login, and run the ntpdate -u 0.ar.pool.ntp.org command on each of them.

Since there's no way I can do this every day because I'm quite busy, the question is exactly how can I create some kind of cron that auto-runs this command every day on each server. I have full root access to all servers, they have CentOs and DirectAdmin. Thanks.-

I have this in my htaccess at the public_html folder of my file server:

RewriteEngine On
RewriteBase /
ReWriteCond %{REQUEST_URI} ^/files/*
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?mysite.net/.*$ [NC]
RewriteRule \.(gif|png|jpg|jar|sis|mp3|thm)$ - [F]

And I have lots of folders and files inside the mysite.net/files dir, which I want to prevent from being direct-downloaded from sites other than mysite.net. However the above rules don't seem to work despite I know that .htaccess file is enabled. In some cases it only blocks the images but no the files. Please tell me what's wrong with that script, or if I can use any other directive to prevent external sites from leeching my files constantly. Thanks

I'm in the need of monitoring in a detailed manner a MySQL dedicated Linux server that is not running apache because it's used for the database exclusively. Is it possible to install the Multi Router Traffic Grapher on it and monitor it from another server?

If not, please suggest any other free monitoring tool as good and simple as MRTG which is a very nice utility, thanks.

I'm running a traffic intense site plenty of dynamic content, mostly user-generated.

The server is a dedicated one and has a total of 4 Intel(R) Xeon(R) CPU X3210 @ 2.13GHz proccesors. I need to know to optimal values for ServerLimit and MaxClients apache's directives, considering that the server has 4GB of RAM and the MySQL database runs on a separate server. The panel is DirectAdmin with CentOS.

Below are my current directives, but during peak hours with over 5k users, an important lag is noticed - and it's not entirey MySQL's fault, because pages seem to be generated fast (I implemented a page generation time counter), but there is a long connection delay until the page starts responding and is sent to the browser.

<IfModule prefork.c>
    StartServers     800
    MinSpareServers   20
    MaxSpareServers   60
    ServerLimit      900
    MaxClients       900
    MaxRequestsPerChild  2000
</IfModule>
Timeout 90
KeepAlive On
KeepAliveTimeout 5

I should mention that monitoring the server using the top command, CPU usage never goes beyond 20% ~ 30% on peak hour. The MySQL server also has a 30~50% usage at that time, and I'm constantly working on fixing slow queries, but that's a different issue. I know it's not a DB bottleneck because static pages also take long to load on peak hours.

Any tips to optimize these values will be greatly appreciated, thanks.