Posts Tagged ‘Cheers’

Linux: List last 10 (newest) and 10 oldest modified files in a directory with ls

Tuesday, April 8th, 2014

An useful thing on GNU / Linux sometimes is to list last or oldest modified files in directory.

Lets say you want to list last 10 modified files with ls from today / yesterday. Here is how:
 

ls -1t | head -10
my.cnf
wordperss_enabled_plugins.txt
newcerts/
mysql-hipo_pcfreakbiz.dump
NewArchive-Jan-10-15.zip
hipo_pcfreakbiz-mysqldb-any-out-1389361234.tgz
Tisho_Snimki/
wordpress/
wp-cron.php?doing_wp_cron=1.1
wp-cron.php

 

To list 10 oldest modified files on Linux:

 

ls -1t | tail -10
    my.cnf
    pcfreak_sql-15_10_05_2012
    mysql-tuning-primer*
    tuning-primer.sh*
    system-administration-services.html
    blog_backup_15_07_2012.tar.gz
    www-files/
    dump.sql
    courier-imap*
    djbdns-1.05.tar.gz


Cheers 😉

How to completely disable Replication in MySQL server 5.1.61 on Debian GNU / Linux

Monday, July 16th, 2012

Replication_mysql_disable

Some time ago on one of the Database MySQL servers, I've configured replication as it was required to test somethings. Eventually it turned out replication will be not used (for some reason) it was too slow and not fitting our company needs hence we needed to disable it.

It seemed logical to me that, simply removing any replication related directives from my.cnf and a restart of the SQL server will be enough to turn replication off on the Debian Linux host. Therefore I proceeded removed all replication configs from /etc/my/my.cnf and issued MySQL restart i. e.:

sql-server:~# /etc/init.d/mysql restart
....

This however didn't turned off replication,as I thought and in phpmyadminweb frontend interface, replication was still appearing to be active in the replication tab.

Something was still making the SQL server still act as an Replication Slave Host, so after a bit of pondering and trying to remember, the exact steps I took to make the replication work on the host I remembered that actually I issued:

mysql> START SLAVE;

Onwards I run:

mysql> SHOW SLAVE STATUS;
....

and found in the database the server was still running in Slave Replication mode

Hence to turn off the db host run as a Slave, I had to issue in mysql cli:

mysql> STOP SLAVE;
Query OK, 0 rows affected, 1 warning (0.01 sec)
mysql> RESET SLAVE;
Query OK, 0 rows affected, 1 warning (0.01 sec)

Then after a reload of SQL server in memory, the host finally stopped working as a Slave Replication host, e.g.

sql-server:~# /etc/init.d/mysql restart
....

After the restart, to re-assure myself the SQL server is no more set to run as MySQL replication Slave host:

mysql> SHOW SLAVE STATUS;
Empty set (0.00 sec)

Cheers 😉

How to set applications (programs) Autorun on XFCE in Xubuntu Linux

Monday, January 16th, 2012

I needed to set TeamViewer to autorun, each and every startup on one Xubuntu Linux

Xubuntu is running by default with Xfce 4 . Xfce is a sort of a very liteweight GNOME like graphical environment.

In Gnome the way that is through invoking the gnome-session-manager .

In Xfce the command is almost analogous doing changes is done by running:

user@xubuntu:~$ xfce4-session-manager

XFce session manager Xubuntu Linux screenshot
Further on simply use the Add button to add applications to load each time user (opens xfce session) / logs in.
Cheers 😉

How to start a process in background and keep it running after the console / terminal is closed on Linux and FreeBSD

Tuesday, November 29th, 2011

The classical way to keep a process running in background after log out of a shell is using screen
Anyways using screen is not the only way to detach a running process , GNU / Linux and BSDs (Free, Open, Net BSDs) had a command nohup which aim is to run a command immune to hangups, with output to a non-tty

Let’s say one wants to keep track (log) constantly ICMP traffic to a certain host with ping command on a UNIX server / desktop which doesn’t have the screen manager … terminal emulation program installed. Achieving this task is possible with nohup cmd by backgrounding the ping process, like so:

guoi@host:~$ nohup ping google.com >ping.log &[1] 45931hipo@host:~$ nohup: ignoring input and redirecting stderr to stdout

Afterwards even after closing up the opened ssh session or console (tty) / terminal (pts) on which the ping process is background nohup prevents the ping to be sent kill SIGNAL so the process continues running in the background.

Later on to check in real time the statistics of the continuous ICMP ping requests tail, less, or cat can be used for example watching the tail:

hipo@host:~$ tail -f ping.log
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=562 ttl=51 time=44.0 ms
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=563 ttl=51 time=43.8 ms
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=564 ttl=51 time=43.3 ms
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=565 ttl=51 time=43.1 ms
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=566 ttl=51 time=43.4 ms
64 bytes from fx-in-f106.1e100.net (74.125.39.106): icmp_req=567 ttl=51 time=43.6 ms

I’m using Linux / BSD for quite a lot of time and never before put in use the nohup cmd I guess there are more ppl who never heard of this handy UNIX basic command. Hope I’m not the only one who never heard about it and its useful knowledge to someone out. Cheers 😉

How to install display and audio drivers on motherboard Asus P5B-Plus with video ATI Radeon HD 2600 XT on Windows XP

Wednesday, November 16th, 2011

Ati Radeon 2600 XT, Display and Audio Drivers download how to

I re-installed one PC with Windows XP which was refusing to boot. The PC had a hardware of:

Motherboard: Asus P5B-Plus
Video Adapter: ATI Radeon HD 2600 XT
Sound card / Sound Blaster:

Ethernet card: Attansic L1 Gigabit Ethernet 10/100/1000Base-T Controller

It took me like 1 hour of search on the Internet and looking through forum threads and sites to properly install all the hardware. In hope to help someone out there looking to install the hardware Window drivers on ATI RAdeon HD 2600 XT, I’ve made a small archive of all the drivers necessery to make the Video card , Sound Card and Ethernet be properly installed and operating.

Here is download link to all the drivers for ATI Radeon HD 2600 XT to run smoothly on Windows XP

Installation of the drivers on Windows is pretty straight forward download the ATI Radeon HD 2600 XT archive extract and install each one of the files contained in the archive. A few restarts will also be necessery after some of the installed drivers to make the drivers work.

ATI Catalyst (included in the archive) will install the Video drivers for the Radeon XT 2600, whether AD1988AB_Audio_V6585_XpVistaWin7 and 11-11_xp32-64_hdmiaudio will install the Audio drivers. Attansic_L1_Lan_V1737907_V10560011159 contained in the archive needs to be extracted and installed to make the Attensic L1 Gigabit ethernet to show up as installed hardware in Windows device manager.

Hope this post will save some time to ppl looking to install the same drivers on XP 😉
Cheers 😉

Adding a nice advanced text editor to make wordpress wp-admin have Microsoft Word like edit functionality

Friday, September 16th, 2011

By the default wordpress does not have support for changing the exact font, therefore copying and pasting a text made in Open Office or MS Word often places in the Post or Page wp edit fonts different from the default one set for articles.
Hence some articles after being published on a wordpress blog show up with improper font and the only way to fix that is to change the font first in Open Office and then copy back to wordpress instead of simply being able to change the font from within the wordpress article.

To get around this problem, there is a nice plugin fckeditor-for-wordpress-plugin which aids wordpress with an awesome Word like edit functionalities.
, downhload location for FCKEdit for WordPress is here

Here is a screenshot of the extra nice functionality the FCKEditor for wordpress providces.

FCKEDitor for wordpress extra functionality screenshot

Installing the plugin is like installing any other wordpress plugin and comes easily to:

debian:/~# cd /var/www/blog/wp-content/plugins
debian:/plugins# wget http://downloads.wordpress.org/plugin/fckeditor-for-wordpress-plugin.3.3.1.zip
...
debian:/plugins# unzip fckeditor-for-wordpress-plugin.3.3.1.zip
...
debian:/plugins# cd fckeditor-for-wordpress-plugin/

And further enabling the plugin from:

Plugins -> Inactive -> (Dean's FCKEditor For WordPress) Enable

fckeditor for wordpress will replace the default wordpress editor TinyMCE straight after being enabled.
 I’ve done also a mirror of the current version as of time of writting of this article, one can  download the fckeditor for wordpress mirrored here 
Now really file editting inside wordpress admin panel is way easier and convenient 😉 Cheers

How to make GRE tunnel iptables port redirect on Linux

Saturday, August 20th, 2011

I’ve recently had to build a Linux server with some other servers behind the router with NAT.
One of the hosts behind the Linux router was running a Window GRE encrypted tunnel service. Which had to be accessed with the Internet ip address of the server.
In order < б>to make the GRE tunnel accessible, a bit more than just adding a normal POSTROUTING DNAT rule and iptables FORWARD is necessery.

As far as I’ve read online, there is quite of a confusion on the topic of how to properly configure the GRE tunnel accessibility on Linux , thus in this very quick tiny tutorial I’ll explain how I did it.

1. Load the ip_nat_pptp and ip_conntrack_pptp kernel module

linux-router:~# modprobe ip_nat_pptp
linux-router:~# modprobe ip_conntrack_pptp

These two modules are an absolutely necessery to be loaded before the remote GRE tunnel is able to be properly accessed, I’ve seen many people complaining online that they can’t make the GRE tunnel to work and I suppose in many of the cases the reason not to be succeed is omitting to load this two kernel modules.

2. Make the ip_nat_pptp and ip_nat_pptp modules to load on system boot time

linux-router:~# echo 'ip_nat_pptp' >> /etc/modules
linux-router:~# echo 'ip_conntrack_pptp' >> /etc/modules

3. Insert necessery iptables PREROUTING rules to make the GRE tunnel traffic flow

linux-router:~# /sbin/iptables -A PREROUTING -d 111.222.223.224/32 -p tcp -m tcp --dport 1723 -j DNAT --to-destination 192.168.1.3:1723
linux-router:~# /sbin/iptables -A PREROUTING -p gre -j DNAT --to-destination 192.168.1.3

In the above example rules its necessery to substitute the 111.222.223.224 ip address withe the external internet (real IP) address of the router.

Also the IP address of 192.168.1.3 is the internal IP address of the host where the GRE host tunnel is located.

Next it’s necessery to;

4. Add iptables rule to forward tcp/ip traffic to the GRE tunnel

linux-router:~# /sbin/iptables -A FORWARD -p gre -j ACCEPT

Finally it’s necessery to make the above iptable rules to be permanent by saving the current firewall with iptables-save or add them inside the script which loads the iptables firewall host rules.
Another possible way is to add them from /etc/rc.local , though this kind of way is not recommended as rules would add only after succesful bootup after all the rest of init scripts and stuff in /etc/rc.local is loaded without errors.

Afterwards access to the GRE tunnel to the local IP 192.168.1.3 using the port 1723 and host IP 111.222.223.224 is possible.
Hope this is helpful. Cheers 😉

Happy System Administrator Day – It’s 31 of July again ;)

Friday, July 29th, 2011

Happy System Administrator’s Day to all Sys Admins, who read my blog regularly! 😉

There are some many mafias around the world, Maybe one day there should be a sysadmin mafia 😉
Cheers! 😉