Posts Tagged ‘occurance’

How to disable nginx static requests access.log logging

Monday, March 5th, 2012

Reading Time: 2minutes

NGINX logo Static Content Serving Stop logging

One of the companies, where I'm employed runs nginx as a CDN (Content Delivery Network) server.
Actually nginx, today has become like a standard for delivering tremendous amounts of static content to clients.
The nginx, server load has recently increased with the number of requests, we have much more site visitors now.
Just recently I've noticed the log files are growing to enormous sizes and in reality this log files are not used at all.
As I've used disabling of web server logging as a way to improve Apache server performance in past time, I thought of implying the same little "trick" to improve the hardware utilization on the nginx server as well.

To disable logging, I proceeded and edit the /usr/local/nginx/conf/nginx.conf file, commenting inside every occurance of:

access_log /usr/local/nginx/logs/access.log main;

to

#access_log /usr/local/nginx/logs/access.log main;

Next, to load the new nginx.conf settings I did a restart:

nginx:~# killall -9 nginx; sleep 1; /etc/init.d/nginx start

I expected, this should be enough to disable completely access.log, browser request logins. Unfortunately /usr/local/nginx/logs/access.log was still displaying growing with:

nginx:~# tail -f /usr/local/nginx/logs/access.log

After a bit thorough reading of nginx.conf config rules, I've noticed there is a config directive:

access_log off;

Therefore to succesfully disable logging I had to edit config occurance of:

access_log /usr/local/nginx/logs/access.log main

to

After a bit thorough reading of nginx.conf config rules, I've noticed there is a config directive:

access_log off;

Therefore to succesfully disable logging I had to edit config occurance of:

access_log /usr/local/nginx/logs/access.log main

to

access_log /usr/local/nginx/logs/access.log main
access_log off;

Finally to load the new settings, which thanksfully this time worked, I did nginx restart:

nginx:~# killall -9 nginx; sleep 1; /etc/init.d/nginx start

And hooray! Thanks God, now nginx logging is disabled!

As a result, as expected the load avarage on the server reduced a bit 🙂

How to change mail sent from in Nagios on Debian GNU/Linux 6

Wednesday, August 24th, 2011

Reading Time: < 1minute
I’ve been playing with configuring a new nagios running on a Linux host which’s aim is to monitor few Windows servers.
The Linux host’s exim is configured to act as relay host to another SMTP server, so all email ending up in the Linux localhost on port 25 is forwarded to the remote SMTP.

The remote smtp only allows the Linux to send email only in case if a real existing username@theserverhostname.com is passed it, otherwise it rejects mail and does not sent properly the email.
As the newly configured Nagios installatio is supposed to do e-mail notification, I was looking for a way to change the default user with which Nagios sends mails, which is inherited directly after the username with which /usr/sbin/nagios3 and /usr/sbin/nrpe are running (on Debian this is nagios@theserverhostname.com).

Thanksfully, there is a work around, I’ve red some forum threads explaning that the username with whch nagios sends mail can be easily changed from /etc/nagios3/commands.cfg by passing the -a “From: custom_user@myserverhostname.com” to all occurance of /usr/bin/mail -s , its preferrable that the -a custom_user@myserverhostname.com is inserted before the -s “” subject option. Hence the occurance of mail command should be changed from:

| /usr/bin/mail -s "** $NOTIFICATIONTYPE$

To:

| /usr/bin/mail -a "From: custom_user@theserverhostname.com" -s "** $NOTIFICATIONTYPE$

Now to read it’s new configurations nagios requirs restart:

debian:~# /etc/init.d/nagios3 restart
...

Now in case of failed services or Hosts Down nagios will send it’s mail from the custom user custom_user@theserverhostname.com and nagios can can send mail properly via the remote relay SMTP host 😉

Error from park wrapper: mydomain.com is already configured. Sorry, that domain is already setup (remove it from httpd.conf) – How to solve

Monday, July 4th, 2011

Reading Time: < 1minute
If you’re administrating a Cpanel server and you come across an error message while trying to use cpanel’s domain addon menu and you want to fix that you will need to do the following logged in as root over an ssh connection:

1. Remove dns related stuff in /var/named and /var/named/cache cpanel:~# rm -f /var/named/mydomain.com.dbcpanel:~# rm -f /var/named/cache/mydomain.com.db

2. Edit the current used httpd.conf on the server and remove all virtualhost domain definitions

cpanel:~# vim /etc/httpd/conf/httpd.conf
# find the mydomain.com Virtualhost definitions and completely remove them

3. Remove any domain occurance in /var/cpanel/users

cpanel:~# cd /var/cpanel/users/
cpanel:/var/cpanel/users# grep -rli 'mydomain.com' *
/var/cpanel/users/hipo
cpanel:~# vim /var/cpanel/users/hipo
# remove in above file any domain related entries

3. Remove anything related to mydomain.com in /etc/userdomains and /etc/localdomains

cpanel:~# vim /etc/userdomains
cpanel:~# vim /etc/localdomains
# again look inside the two files and remove the occuring entries

4. Edit /etc/named.conf and remove any definitions of mydomain.com

cpanel:~# vim /etc/named.conf
# in above file remove DNS configuration for mydomain.com

5. Run /scripts/updateuserdomains

cpanel:~# /scripts/updateuserdomains

6. Delete any valias configurations

cpanel:~# rm -f /etc/valiases/mydomain.com
cpanel:~# rm -f /etc/vdomainaliases/mydomain.com
cpanel:~# rm -f/etc/vfilters/mydomain.com

7. Remove any occurance of mydomain.com in the user directory which experiences the Error from park wrapper: error

Let’s say the user testuser is experiencing the error, in that case you will have to remove:

cpanel:~# rm -rf /home/testuser/public_html/mydomain.com

8. Restart Cpanel

This step is optional though I think it’s also a good practice as it will at least restart the Cpanel webserver (Apache or Litespeed depending on your conf)

cpanel:~# /etc/init.d/cpanel restart

Now try to add up the domain via the Cpanel domain addon interface, hopefully the issue should be fixed by now. If not you might also check if there is no some record about mydomain.com in the mysql server.
Cheers 😉

How to fix wicd 1.7.0+ds1-5 Connection Failed: Bad Password on Ubuntu 10.10 (Maverick Merkaaat)

Tuesday, May 3rd, 2011

Reading Time: < 1minute
I’ve been struggling with fixing a nasty error with wicd network manager for about 2 hours.
The exact error message I faced was:

Connection Failed: Bad Password

The issue occured after some suggested updates from the Ubuntu graphical update tool.
The wireless network to which it was connected was a WPA-PSK (WPA2) Passphrase authentication.
The network key was properly typed in and was working well on another system so the error Connection Failed: Bad Password made no sense.

There was nothing unusual in /var/log/wicd/wicd.log , that made me even more curious about what might be causing the error.After a lot of try outs and a lot of readings and tests I finally got the cause of the weird Bad Password errors produced by wicd

Weirdly enought, somehow the Ubuntu package update tool has installed the default gnome network-manager package.
The installed network-manager package has mismatched somehow the way wicd connects to wireless networks and as a cause the wpa_supplicant binary was not properly invoked.

As a consequence of the network-manager being present on the system the wpa_supplicant process which made the exact connection to the wireless network was not launching in, the exact wpa_supplicant invocation missing was:

wpa_supplicant -B -i wlan0 -c /var/lib/wicd/configurations/0022b0aa424a -D wext

Luckily the solution to the notebook wireless device unable to connect to the Wireless network was simple.

All I had to do is completely remove all occurance of network-manager packages installed on the Ubuntu system, by issuing the commands:

ubuntu:~# apt-get remove --yes network-manager
ubuntu:~# dpkg --purge network-manager-pptp-gnome network-manager-pptp network-manager

The reason for issuing the a dpkg –purge command was my desire to completely get rid of all kind of network-manager related configurations.

Now after re-connecting with wicd wireless manager, it worked fine 😉