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    Adding secondary FTP user for a domain in plesk control panel

    February 21st, 2011

    Hi,

    Finally you came here to know how to create additional FTP user account for a domain in plesk control panel, no wonder i will explain you its pretty simple, all you need is to be root of the server.

    Let’s get started.

    Login to the server using root account and add a user which you need to restrict the files/folders that the user can access by using the following command.

    #useradd -d /var/www/vhosts/domainname.tld/path/to/folder/

    now a user will be created, but the user can access other files under / partition where the server has read permission to other users, this is a big security hole so you need make sure that the user shouldn’t access other files in the server except the folder which he should access. So, you have to change change the group id for that particular user, this can be done by following the steps below.

    All the user details will be in /etc/passwd file, there you need to change the group id from
    username:x:500:500::/var/www/vhosts/domainname.tld/path/to/folder/:/bin/bash
    username1:x:501:501::/var/www/vhosts/domainname.tld/path/to/folder/:/bin/bash

    to

    username:x:500:2425::/var/www/vhosts/domainname.tld/path/to/folder/:/bin/bash

    [ Above I have changed the group id(500) to 2425 which is the default psactl group id for Plesk control panel it may differ for your server, you can check it with other FTP user names and use that for the new user]

    Now you should also change the shell for the user which is currently set to user as/bin/bash, where the user can access the server using SSH, you need to change it to /bin/false which will make the user to use only FTP service.

    That’s it, a new FTP user is created in Plesk control panel.

    Thank you for viewing helpinlinux.com

    1 Comment "

    MySQL version downgrade in linux cPanel servers

    February 21st, 2011

    SOP for MySQL version downgrade from 5.1 to 4.0 in cPanel servers
    ================================================
    Pre-installation steps
    ==============

    Before you downgrade the MySQL version you need to do the following steps so as to avoid data loss or file corruption

    Check the MySQL version by using the following command

    #rpm -qa |grep MySQL

    O/P
    MySQL-server-5.0.91-0.glibc23
    MySQL-client-5.0.91-0.glibc23
    MySQL-devel-5.0.91-0.glibc23
    MySQL-shared-5.0.91-0.glibc23
    MySQL-bench-5.0.91-0.glibc23

    check the server OS as below

    # cat /etc/issue
    or
    # cat /etc/redhat-release

    O/P
    CentOS release 5.5 (Final)

    Server architecture check

    # arch

    O/P
    x86_64

    Before downgrading we need to backup MySQL databases so as to avoid data corruption so we are copying the mysql database folder by using the following command

    #cp -arp /var/lib/mysql /var/lib/mysql.bak

    then dump the mysql databases using the following command

    #mysqldump -u root -p(password) –all-databases > dumpfilename.sql

    You can also take version compatible downgrade dump to check for any missing file restoring by using the following command

    #mysqldump -u root -p(password) –all-databases –compatible=mysql40 > versioncompatibledumpfilename.sql

    Actual MySQL down-gradation
    ===================

    Then now we can start the down-gradation process

    First you need to open the cpanel.conf file and make changes to the MySQL-version line from 5.1 to 4.0 by following the using the command

    #vi /var/cpanel/cpanel.config

    After changing the MySQL version line from 5.1 to 4.0 in the configuration file we need to run the following command to force the MySQL up-gradation/Down-gradation.

    #/scripts/mysqlup –force

    Now the MySQL version down-gradation will take place, once the process is completed you can check the version of MySQL which will be

    # rpm -qa | grep -i mysql-
    O/P

    MySQL-shared-4.0.27-0
    MySQL-devel-4.0.27-0
    MySQL-bench-4.0.27-0
    MySQL-client-4.0.27-0
    MySQL-embedded-4.0.27-0
    MySQL-server-4.0.27-0

    Restart MySQL services by using the following command
    #/etc/init.d/mysql restart

    That’s all the MySQL version has been downgraded successfully.

    Thank you for viewing helpinlinux.com

    9 Comments "

    Form mail issue with php script.

    February 21st, 2011

    If you are getting the following error message

    ** user@domain.com R=virtual_aliases: No Such User Here

    Please remove the domain name from /etc/localdomains

    and add the domain to /etc/remotedomains.

    This will fix the problem as the domain has MX record outside the server the form mail on the server won’t try to send mail, if you change these two files, it will fix the problem.

    If you receive any error as below

    2010-10-30 12:19:52 1PCF5s-00037s-3x ** user@anydomain.com R=lookuphost T=remote_s mtp: SMTP error from remote mail server after MAIL FROM: SIZE=1415: host MX.anydomain.com [xxx.xxx.xxx.xxx]: 553 #5.1.8 Domain of sender address does not exist

    then

    Goto php.ini file and add the following line

    “sendmail_path =/usr/sbin/sendmail -t -i -f mailer@yourdomain.com”

    Thank you for viewing helpinlinux.com

    No Comments "

    Installing eAccelerator in linux machine

    February 21st, 2011

    Follow the steps to install eAccelerator in linux machine

    #cd /usr/local/
    #wget http://bart.eaccelerator.net/source/0.9.6/eaccelerator-0.9.6-rc1.tar.bz2
    #tar -jxvf eaccelerator-0.9.6-rc1.tar.bz2
    #cd /usr/local/eaccelerator-0.9.6-rc1/
    #phpize
    #./configure
    #make
    #make install

    Open a file as eaccelarator.ini in /etc/php.d/ directory

    #vi /etc/php.d/eaccelarator.ini

    Then add the configuration like :

    zend_extension=”path/where/eaccelerator.so/is/locate/eaccelerator.so”
    eaccelerator.shm_size=”16″
    eaccelerator.cache_dir=”/tmp/eaccelerator”
    eaccelerator.enable=”1″
    eaccelerator.optimizer=”1″
    eaccelerator.check_mtime=”1″
    eaccelerator.debug=”0″
    eaccelerator.filter=””
    eaccelerator.shm_max=”0″
    eaccelerator.shm_ttl=”0″
    eaccelerator.shm_prune_period=”0″
    eaccelerator.shm_only=”1″
    eaccelerator.compress=”1″
    eaccelerator.compress_level=”9″

    save and exit.

    Make the cache directory

    #mkdir /tmp/eaccelerator
    #chmod 777 /tmp/eaccelerator/

    Restart http service

    #/etc/init.d/httpd restart

    test the installation using

    Testink

    #php -v

    You should be getting a output like

    PHP 5.3.0 (cli) (built: Nov 1 2009 22:38:48)
    Copyright (c) 1997-2009 The PHP Group
    Zend Engine v2.3.0, Copyright (c) 1998-2009 Zend Technologies
    with eAccelerator v0.9.6-rc1, Copyright (c) 2004-2007 eAccelerator, by eAccelerator

    That’s it, you have installed eAccelerator on the server.

    1 Comment "

    Steps to add a new domain in Hsphere control panel

    February 21st, 2011

    Following are the steps to add a domain name to your Hsphere Control panel account.

    1. Login to your control panel.

    2. Select Domains icon.

    3. You will be taken to a page where you will have an option to add a domain, select that option.

    4. There you will have three options
    a.Domain Name Registration-Can be used when you didn’t register a domain.
    b.Host Existing Site-Can be used when you already registered a domain.
    c.Third Level Domain Name Registration-Something like a sub domain used in conjunction with service provider’s name as second level domain name(say yourdomain.serviceprovider.com).

    5. Fill the required field and select Submit.

    6. Now your new domain will be added.

    No Comments "

    Removing Zombie process in the server

    February 21st, 2011

    Hi,

    I have got a solution for removing zombie process on servers(linux servers). We neither
    need to restart the server nor run script to do this all we have to do is
    just run the following command.

    ps -el | grep 'Z'
    
    The output of the above command will be something like this
    
    F S   UID   PID  PPID  C PRI  NI ADDR SZ WCHAN  TTY          TIME CMD
    4 Z     0   668  4243  0  78   0 -     0 exit   ?        00:09:39 VV
    4 Z     0  1403  4243  0  78   0 -     0 exit   ?        00:08:11 VV
    4 Z     0  1613  4243  0  78   0 -     0 exit   ?        00:09:43 VV
    4 Z     0  2202  4243  0  78   0 -     0 exit   ?        00:09:25 VV
    4 Z     0  2382  4243  0  82   0 -     0 exit   ?        00:08:07 VV
    4 Z     0  2618  4243  0  78   0 -     0 exit   ?        00:09:52 VV
    4 Z     0  2714  4243  0  77   0 -     0 exit   ?        00:09:51 VV
    4 Z     0  2741  4243  0  78   0 -     0 exit   ?        00:09:18 VV
    4 Z     0  2956  4243  0  76   0 -     0 exit   ?        00:07:41 VV
    4 Z     0  3030  4243  0  75   0 -     0 exit   ?        00:00:06 VV
    4 Z     0  3125  4243  0  83   0 -     0 exit   ?        00:08:09 VV
    4 Z     0  3260  4243  0  83   0 -     0 exit   ?        00:09:02 VV
    4 Z     0  3480  4243  0  77   0 -     0 exit   ?        00:09:37 VV
    4 Z     0  4151  4243  0  76   0 -     0 exit   ?        00:08:49 VV
    4 Z     0  4899  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0  5099  4243  0  81   0 -     0 exit   ?        00:09:32 VV
    4 Z     0  5667  4243  0  76   0 -     0 exit   ?        00:07:58 VV
    4 Z     0  5778  4243  0  78   0 -     0 exit   ?        00:09:40 VV
    4 Z     0  5956  4243  0  82   0 -     0 exit   ?        00:10:19 VV
    4 Z     0  7035  4243  0  80   0 -     0 exit   ?        00:10:04 VV
    4 Z     0  7448  4243  0  83   0 -     0 exit   ?        00:08:23 VV
    4 Z     0  7757  4243  0  83   0 -     0 exit   ?        00:10:06 VV
    4 Z     0  8219  4243  0  82   0 -     0 exit   ?        00:10:11 VV
    4 Z     0  8262  4243  0  76   0 -     0 exit   ?        00:07:55 VV
    4 Z     0  8631  4243  0  76   0 -     0 exit   ?        00:05:57 VV
    4 Z     0  8728  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0  8944  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0  9431  4243  0  80   0 -     0 exit   ?        00:09:57 VV
    4 Z     0  9577  4243  0  83   0 -     0 exit   ?        00:09:00 VV
    4 Z     0  9762  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 10263  4243  0  76   0 -     0 exit   ?        00:07:57 VV
    4 Z     0 10960  4243  0  83   0 -     0 exit   ?        00:08:13 VV
    4 Z     0 11526  4243  0  78   0 -     0 exit   ?        00:10:08 VV
    4 Z     0 11952  4243  0  78   0 -     0 exit   ?        00:08:05 VV
    4 Z     0 13339  4243  0  78   0 -     0 exit   ?        00:08:12 VV
    4 Z     0 14776  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 15016  4243  0  83   0 -     0 exit   ?        00:08:09 VV
    4 Z     0 15163  4243  0  76   0 -     0 exit   ?        00:07:44 VV
    4 Z     0 16673  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 17057  4243  0  79   0 -     0 exit   ?        00:09:33 VV
    4 Z     0 17095  4243  0  75   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 17155  4243  0  81   0 -     0 exit   ?        00:09:44 VV
    4 Z     0 17760  4243  0  81   0 -     0 exit   ?        00:09:42 VV
    4 Z     0 18088  4243  0  83   0 -     0 exit   ?        00:10:00 VV
    4 Z     0 18274  4243  0  76   0 -     0 exit   ?        00:07:45 VV
    4 Z     0 18744  4243  0  83   0 -     0 exit   ?        00:09:18 VV
    4 Z     0 19227  4243  0  82   0 -     0 exit   ?        00:10:10 VV
    4 Z     0 19288  4243  0  79   0 -     0 exit   ?        00:09:23 VV
    4 Z     0 19316  4243  0  78   0 -     0 exit   ?        00:09:51 VV
    4 Z     0 19654  4243  0  78   0 -     0 exit   ?        00:09:32 VV
    4 Z     0 19695  4243  0  77   0 -     0 exit   ?        00:09:51 VV
    4 Z     0 20190  4243  0  78   0 -     0 exit   ?        00:08:55 VV
    4 Z     0 20602  4243  0  76   0 -     0 exit   ?        00:07:56 VV
    4 Z     0 21455  4243  0  76   0 -     0 exit   ?        00:07:54 VV
    4 Z     0 21687  4243  0  83   0 -     0 exit   ?        00:09:16 VV
    4 Z     0 22785  4243  0  84   0 -     0 exit   ?        00:08:08 VV
    4 Z     0 22855  4243  0  78   0 -     0 exit   ?        00:09:39 VV
    4 Z     0 23330  4243  0  78   0 -     0 exit   ?        00:09:37 VV
    4 Z     0 23405  4243  0  82   0 -     0 exit   ?        00:10:24 VV
    4 Z     0 23600  4243  0  83   0 -     0 exit   ?        00:08:45 VV
    4 Z     0 24578  4243  0  76   0 -     0 exit   ?        00:07:40 VV
    4 Z     0 24846  4243  0  75   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 25661  4243  0  78   0 -     0 exit   ?        00:08:04 VV
    4 Z     0 26718  4243  0  76   0 -     0 exit   ?        00:07:56 VV
    4 Z     0 26908  4243  0  82   0 -     0 exit   ?        00:09:45 VV
    4 Z     0 27554  4243  0  77   0 -     0 exit   ?        00:09:27 VV
    4 Z     0 28478  4243  0  82   0 -     0 exit   ?        00:08:10 VV
    4 Z     0 28553  4243  0  78   0 -     0 exit   ?        00:10:21 VV
    4 Z     0 29034  4243  0  76   0 -     0 exit   ?        00:09:24 VV
    4 Z     0 29173  4243  0  82   0 -     0 exit   ?        00:09:54 VV
    4 Z     0 29193  4243  0  82   0 -     0 exit   ?        00:09:04 VV
    4 Z     0 29722  4243  0  78   0 -     0 exit   ?        00:09:34 VV
    4 Z     0 30856  4243  0  78   0 -     0 exit   ?        00:09:11 VV
    4 Z     0 30999  4243  0  83   0 -     0 exit   ?        00:09:04 VV
    4 Z     0 31057  4243  0  78   0 -     0 exit   ?        00:09:51 VV
    4 Z     0 31274  4243  0  76   0 -     0 exit   ?        00:07:51 VV
    4 Z     0 31735  4243  0  76   0 -     0 exit   ?        00:00:04 VV
    4 Z     0 31924  4243  0  81   0 -     0 exit   ?        00:08:01 VV
    4 Z     0 32121  4243  9  78   0 -     0 exit   ?        00:10:11 VV 
    

    then we have to look into PPID(parent process i’d) and kill that process,

    here the PPID is 4243

    so the command to be executed will be

     kill -9 4243

    Thank you for viewing helpinlinux.com

    2 Comments "

    Installing SSL for a domain

    February 21st, 2011

    Installing SSL through WHM for a particular domain
    =======================================

    1. Login to your WHM panel.
    2. Select “SSL/TLS” icon on the WHM panel.
    3. You will be taken to a new page there please select “Generate a SSL certificate and Signing request”.
    4. Fill all the required fields and select Create.
    5. A encrypted version of your CSR and RSA key will be generated and a copy of these two will also be sent to the mentioned email address.
    6. Please take these two(CSR and RSA) to your SSL vendor to purchase a SSL certificate for you and come back to proceed further.
    7.Select “Install SSL certificate and setup a domain” icon from “SSL/TLS”.
    8. Please place the SSL certificate inside the free space and then select Domain name,username and IP address of the particular domain and select “Do it”.
    9. That’s all your SSL will be installed on the server.

    Installing SSL for a domain through server
    ===================================

    1. Login to your linux system/server and goto /usr/share/ssl.
    2. Here you will have all the files/folders required for ssl installation.
    3. Copy the crt file at /usr/share/ssl/cert/domain.crt.
    4. Copy the key file in /usr/share/ssl/private/domain.key
    5. Copy the CA bundle at /usr/share/ssl/cert/domain.ca
    6. Sample virtual host entry for ssl at httpd.conf

    ServerName domain.com
    ServerAlias www.domain.com
    DocumentRoot /home/username/public_html
    ServerAdmin webmaster@domain.com
    UseCanonicalName off
    UserDir public_html

    suPHP_UserGroup username username

    User username
    Group usergroup

    BytesLog /usr/local/apache/domlogs/domain.com-bytes_log
    ScriptAlias /cgi-bin/ /home/username/public_html/cgi-bin/
    SSLEngine on
    SSLCertificateFile /usr/share/ssl/certs/www.domain.com.crt
    SSLCertificateKeyFile /usr/share/ssl/private/www.domain.com.key
    SSLCACertificateFile /usr/share/ssl/certs/www.domain.com.cabundle
    CustomLog /usr/local/apache/domlogs/domain.com-ssl_log combined
    SetEnvIf User-Agent “.*MSIE.*” nokeepalive ssl-unclean-shutdown

    Thank you for viewing helpinlinux.com

    No Comments "

    Telnet in Linux

    February 21st, 2011

    Telnet is developed focusing on client to server connection for data transfer. Telnet connects to the server in a plain text format. It was developed in 1969, due to security drawbacks it has been replaced by SSH in 1995.

    To check whether telnet is active in your system use this following command in RHEL3/4.

    [user@linux]# chkconfig telnet on
    [user@linux]# service xinetd reload 

    For fedora core1

    Linux is configured to run the Telnet and FTP server, but by default, these services are not enabled. To enable the telnet these service, login to the server as the root userid and edit the files:

    [user@linux]#/etc/xinetd.d/telnet

    In this file, find the line for disable and change it from the value “yes” to “no”.

    To connect to telnet we use the following command in linux

    [user@linux]#telnet

    To limit number parallel of telnet connections we shall reduce the following pts connections in the file /etc/securetty.

    pts0

    pts1

    pts2

    pts3

    pts4

    pts5


    The above output will have 6 parallel telnet connections.

    reference: http://www.idevelopment.info/data/Unix/Linux/LINUX_TelnetFTPAsRoot.shtml

    en.wikipedia.org

    1 Comment "

    Commonly used port numbers

    February 21st, 2011

    The following are the frequently used port numbers.

    FTP data transfer mode – 20
    FTP control(command) mode – 21
    SSH – 22.
    Telnet – 23..
    WHOIS – 43.
    DNS – 53

    NNTP(Network news Transfer Protocol)-119

    Web service port numbers
    ======================
    http-80
    Mysql-3306
    https-443

    Control panel default port numbers
    ============================
    cPanel – 2082
    secure cPanel – 2083
    WHM -2086
    secure WHM -2087
    webmail – 2095
    secure webmail – 2096
    Plesk – 8443,8087
    Webmin-10000

    Mail port numbers
    ==============
    IMAP-143
    POP2-109
    POP3-110
    SMTP-25
    IMAPS-993
    SMTPS-465

    Reference -en.wikipedia.org

    No Comments "

    hotlink protection in apache server

    February 21st, 2011

    This can be accomplished with a combination of SetEnvIf and the Deny and Allow directives. However, it is important to understand that any access restriction based on the REFERER header is intrinsically problematic due to the fact that browsers can send an incorrect REFERER, either because they want to circumvent your restriction or simply because they don’t send the right thing (or anything at all).

    The following configuration will produce the desired effect if the browser passes correct REFERER headers.

    SetEnvIf REFERER "www\.mydomain\.com" linked_from_here
    SetEnvIf REFERER "^$" linked_from_here
    
       Order deny,allow
       Deny from all
       Allow from env=linked_from_here

    Reference: http.apache.org

    Thank you for viewing helpinlinux.com

    1 Comment "