Vim Recording

Ref: http://www.thegeekstuff.com/2009/01/vi-and-vim-macro-tutorial-how-to-record-and-play/

Start recording by pressing q, followed by a lower case character to name the macro
Perform any typical editing, actions inside Vim editor, which will be recorded
Stop recording by pressing q
Play the recorded macro by pressing @ followed by the macro name
To repeat macros multiple times, press : NN @ macro name. NN is a number

32-bit and 64-bit packages in CentOS 5 x86_64

yum -y remove *.i386 *.i486 *.i586 *.i686

*Not recommended but you can prevent yum from installing 32-bit software by adding this line to section [main] in /etc/yum.conf:
exclude=*.i386 *.i586 *.i686

MySQL (RHEL5)

chkconfig mysqld on
/etc/init.d/mysqld start
Login mysql
CREATE USER 'user1'@'localhost' IDENTIFIED BY 'passpass'; (passpass is the password you use to login)
DROP USER 'user2'@'localhost'
GRANT ALL ON *.* TO 'user1'@'localhost'; (wildcard % is allowed for * match)
USE mysql
UPDATE user SET password=PASSWORD("passpass") WHERE User='user1';
FLUSH PRIVILEGES;

Modify MySQL configuration file (/etc/my.cnf for Fedora-based linux; /etc/mysql/my.cnf for Debian-based linux), so it looks like this:

[client]
max_allowed_packet=1024M
[odbc]
max_allowed_packet=1024M
[mysqld]
max_allowed_packet=1024M
slave_transaction_retries=128
default-storage-engine=INNODB
datadir=/mnt/MD_1000/mysql
user = mysql
socket = /var/run/mysqld/mysqld.sock
port = 3306

Open port 3306 for remote administration:
/sbin/iptables -A INPUT -i eth0 -p tcp --destination-port 3306 -j ACCEPT
Or if the only allowed client (e.g. your web server) is 10.5.1.3, then:
/sbin/iptables -A INPUT -i eth0 -s 10.5.1.3 -p tcp --destination-port 3306 -j ACCEPT

Save iptables rules:
service iptables save

Backup/dumping with limited rows (e.g. to build a sample database from a large one)
mysqldump -u [username] -p [databaseName] --where="true limit 100" > dump.sql

Linux List The Open Ports And The Process That Owns Them

Ref: http://www.cyberciti.biz/tips/linux-display-open-ports-owner.html

How do you list the network open ports on your server and the process that owns them? The answer is simple use the following command (must run as root):

sudo lsof -i
sudo netstat -lptu

CentOS 5 FTP Setup (vsftpd)

Ref 1: http://www.linuxquestions.org/questions/fedora-35/vsftpd-error-553-could-not-create-file-390569
Ref 2: http://www.cyberciti.biz/tips/rhel-fedora-centos-vsftpd-installation.html

Disable SELinux on FTP, so that uploading works:
setsebool -P ftp_home_dir 1

Install the vsftpd package via yum command:
# yum install vsftpd

vsftpd Defaults

Default port: TCP / UDP - 21 and 20
The main configuration file: /etc/vsftpd/vsftpd.conf
Users that are not allowed to login via ftp: /etc/vsftpd/ftpusers

Configure Vsftpd Server

# vi /etc/vsftpd/vsftpd.conf

Turn off standard ftpd xferlog log format:
xferlog_std_format=NO
Turn on verbose vsftpd log format. The default vsftpd log file is /var/log/vsftpd.log:
log_ftp_protocol=YES
Above to directives will enable logging of all FTP transactions. Lock down users to their home directories:
chroot_local_user=YES
Create warning banners for all FTP users:
banner_file=/etc/vsftpd/issue
Turn on vsftpd on boot:
# chkconfig vsftpd on
Start the service:
# service vsftpd start
# netstat -tulpn | grep :21

Configure Iptables To Protect The FTP Server

# vi /etc/sysconfig/iptables
Add the following lines, ensuring that they appear before the final LOG and DROP lines for the RH-Firewall-1-INPUT:
-A RH-Firewall-1-INPUT -m state --state NEW -p tcp --dport 21 -j ACCEPT
Open file /etc/sysconfig/iptables-config, enter:
# vi /etc/sysconfig/iptables-config
Ensure that the space-separated list of modules contains the FTP connection tracking module:
IPTABLES_MODULES="OTHER_MODULES ip_conntrack_ftp"
Save and close the file. Restart firewall:
# service iptables restart

Tip: View FTP Log File
Type the following command:
# tail -f /var/log/vsftpd.log

Tip: Restrict Access to Anonymous User Only
Edit the vsftpd configuration file /etc/vsftpd/vsftpd.conf and add the following:
local_enable=NO

Tip: Disable FTP Uploads
Edit the vsftpd configuration file /etc/vsftpd/vsftpd.conf and add the following:
write_enable=NO

For upload to work except for anonymous, you might need to:

• create a group, say ftpw
• change the ownership of /var/ftp and its subdirectories to group ftpw
• add ftpw group onto users with write privilege

Notes on Compiling SeqHound

1. Compile NCBI
   1. make sure link the actual makefile in platform/ to the root level
   2. make sure the paths in the linked makefile are modified to your environment
2. Compile SLRI
   1. make sure $NCBI is set
   2. link lib/*.mk to root level
   3. cd lib && make lib
3. Compile bzip2
4. Compile libiodbc (as ODBC dependency)
5. Set environment var $NCBI, $SLRI, $ODBC, and $BZDIR
6. Comment out ValNodeUnique in seqhound/include/intrez_misc.h and seqhound/src/intrez_misc.c
7. cd seqhound && ./makeallsh odbc all

Secure GRUB

Version 1 (aka 0.98)
Reference cyberciti.biz

1. #grub-md5-crypt
Password:
Retype password:
$1$NYoR71$Sgv6pxQ6LG4GXpfihIJyL0

2. # vi /boot/grub/menu.lst (Red Hat /boot/grub/grub.conf)
   Edit file and add a password line as follows:
   password --md5 $1$NYoR71$Sgv6pxQ6LG4GXpfihIJyL0

Sample config file:
default 0
timeout 5
password --md5 $1$NYoR71$Sgv6pxQ6LG4GXpfihIJyL0
title Debian GNU/Linux, kernel 2.6.13.4-cust-en-smp
root (hd0,0)
kernel /boot/vmlinuz root=/dev/hda3 ro
savedefault
boot

Version 2 (aka 1.98)
Reference ubuntuforums.org

Linux notes

skill -STOP -u username Pause somebody.
skill -KILL -u username Kick out somebody.
skill -KILL -v /dev/pts/* Kick all out.

last show successful logins
lastb show bad logins
lastlog show latest logins of all/any users.
/var/log/btmp bad logins
/var/log/wtmp successful logins
/var/run/utmp current logins

Set date and time
# date -s "2 OCT 2006 18:00:00"
# date --set="2 OCT 2006 18:00:00"
# date +%Y%m%d -s "20081128"
# date +%T -s "10:13:13"

Get hardware info
/sbin/lspci
/sbin/lsusb
lshw

route -n
shows the routing table, the gateway will be flagged with a 'G'

If DNS is not properly configured, go to /etc/resolv.conf, check or add line nameserver x.x.x.x

To pipe wget download content:
wget -q url -O - | cat > abc.txt

For ubuntu 10.10
Edit /etc/default/grub & run update-grub to set the booting preferences

Ubuntu Server 10.10 (As desktop use)

Hate OpenOffice? Dislike the integrated IM software? Feel sick about GNOME games? This solution might help to build the desktop from scratch that avoids most unnecessary components.

Installation:

1. Get a ubuntu server iso, and install it the debian way.
2. Modify /etc/apt/sources.list to your satisfaction.
3. Configure Medibuntu source: https://help.ubuntu.com/community/Medibuntu

Addition:

• Basic:
  • vim
• Desktop:
  • xserver-xorg
  • gnome-core
  • gdm
  • gnome-themes-selected
  • humanity-icon-theme
  • gcalctool (the calculator)
  • chromium-browser
  • gnome-screensaver
  • flashplugin-installer
  • language-support-??
  • *network-manager
  • *network-manager-openconnect (for Cisco AnyConnect VPN)
  • *wine
• Security:
  • vlock
• Development:
  • g++
  • openjdk-6-jre
  • qt4-dev-tools
  • *dia
  • *mysql-server
  • *mysql-admin
  • *python-mysqldb
• Remote access:
  • vinagre (the client)
  • vino (the server)
• Media:
  • vlc
  • mozilla-plugin-vlc
  • libdvdcss2
  • ubuntu-restricted-extras
• Printing:
  • system-config-printer-gnome
  • cups
  • *smbclient (for Windows shared printing)
  • *hplip (HP printer drivers)

Configuration:

• Clear screen when logout:
  1. ~/.bash_logout
  2. insert single command clear
• Disable Ctrl-Alt-Del:
  1. /etc/init/control-alt-delete.conf
  2. comment out the actual command line
• Secure login/out logs:
  1. sudo chmod 640 `sudo find /var -name ?tmp`
• Stop GDM from auto starting:
  1. /etc/init/gdm.conf
  2. comment out all "start on" stuff
• Configure GRUB:
  1. /etc/default/grub
  2. update-grub
• MySQL
  1. /etc/mysql/my.cnf
  2. to reset root password: sudo dpkg-reconfigure mysql-server-5.1

Building CLucene

Note: done on Ubuntu 10.10.
Note 2: if no need for snapshot features, there is a pre-built package in the repo, called libclucene-dev.

Download CLucene source (tgz).

Install necessary dependency for building:

• g++
• zlib1g-dev
• cmake

Make a new folder, and cd into it. Run cmake <clucene-source-folder>.
Then ccmake <clucene-source-folder> to turn on static library build.

If you get an error complaining undeclared INT_MAX in file src/core/CLucene/search/spans/TermSpans.cpp, insert #include <limits.h> at the beginning of that file.