i-net.com.au http://www.i-net.com.au P. 1300 763 304 Tue, 15 May 2012 04:36:27 +0000 en hourly 1 http://wordpress.org/?v=3.3.2 Secure your Virtual Private Server (VPS) http://www.i-net.com.au/2011/04/03/secure-your-virtual-private-server-vps/ http://www.i-net.com.au/2011/04/03/secure-your-virtual-private-server-vps/#comments Sun, 03 Apr 2011 04:37:45 +0000 admin http://www.i-net.com.au/?p=1536 Secure your Virtual Private Server (VPS)

We do not provide any warranty for this article, so if you are not sure what you are doing please make sure you research before you do it.

First Update OS and Software:

Update cPanel, Apache & other installed software to latest stable version. Generally, with later versions there are bug fixes and security patches that need to be applied

Secure cPanel/WHM and the Root User on VDS:

Checking for formmail:

Form mail is used by hackers to send out spam email, by relay and injection methods. If you are using matts script or a version of it, you may be in jeopardy.

Command to find pesky form mails:

find / -name “[Ff]orm[mM]ai*”

CGIemail is also a security risk:

find / -name “[Cc]giemai*”

Command to disable form mails:

chmod a-rwx /path/to/filename

(a-rwx translates to all types, no read, write or execute permissions).

(this disables all form mail)

If a client or someone on your vps installs form mail, you will have to let them know you are disabling their script and give them an alternative.

Root kit Checker (rkhunter or chkrootkit)

Check for a root kits via a cron job, by doing this you will regularly check if your server is comprised, and you will be sent regular reports.

To install chkrootkit, login to the server as root and on the command line interface type:

cd /root/

wget ftp://ftp.pangeia.com.br/pub/seg/pac/chkrootkit.tar.gz

tar xvzf chkrootkit.tar.gz

cd chkrootkit-0.47

make sense

To run chkrootkit, type the following on the CLI:

/root/chkrootkit-0.47/chkrootkit

To ensure the highest level of security setup a cronjob which emails you the results on a regular basis. Setup Email on Root Login (to detect breaches)

If an unauthorized person gains access to root, you want to be notified – you can do so by doing the following while logged into root:

cd /root

vi .bash_profile

Add the following line:

echo ‘ALERT – Root Shell Access on:’ `date` `who` | mail -s “Alert: Root Access from `who | awk ‘{print $6}’`” your@email.com

Where your@email.com is your email address.

Save an exit vi: :wq

To change the SSH Legal Message (displayed when you login via SSH), edit /etc/motd to display the message you wish to show. Securing WHM and cPanel:

By default cPanel/WHM is not setup securely and efficiently, so you will want to optimize the cPanel/WHM settings by doing the following:

Go to: Server Setup -> Tweak Settings

Under Domains tick:

· Prevent users from parking/adding common internet domains (hotmail.com, aol.com, etc)

Under Mail tick:

· Attempt to prevent pop3 connection floods

· Default catch-all/default address behavior for new accounts – set this to FAIL

Under System tick:

· Use jailshell as default on new accounts

Go to: Server Setup -> Tweak Security

· Enable php open_basedir protection

· Enable mod_userdir protection

· Disable compilers for unprivileged users

Go to: Server Setup -> Shell Fork Bomb Protection

· Enable shell bomb/memory protection

When creating reseller packages, be sure to:

· Disallow creation of packages with shell acces

· Disallow creation of packages with full root access

Go to: Service Configuration -> FTP Configuration

· Disable anonymous FTP access

Go to: Account functions -> Manage Shell Acess

· Disable shell access for all users (except yourself)

Go to: MySQL -> Manage Root Password

· Change Root Password for MySQL

Go to: Security -> Quick Security Scan for Trojan Horses, and make sure you don’t have any of the following infected:

· /sbin/depmod

· /sbin/insmod

· /sbin/insmod.static

· /sbin/modinfo

· /sbin/modprobe

· /sbin/rmmod General OS Security (do not need to be running cPanel):

Restict SSH access: For improved security

Also see http://www.webhostingtalk.com/showthread.php?t=468168 & http://forums.deftechgroup.com/showthread.php?t=26&highlight=secure+vps for more security info

]]> http://www.i-net.com.au/2011/04/03/secure-your-virtual-private-server-vps/feed/ 1 Linux Cheat Sheet http://www.i-net.com.au/2011/04/03/linux-cheat-sheet/ http://www.i-net.com.au/2011/04/03/linux-cheat-sheet/#comments Sun, 03 Apr 2011 03:22:47 +0000 admin http://www.i-net.com.au/?p=1529 This is a linux command line cheat sheet. All these commands have been tested both on Centos.

For mac users you can SSH into your Server using Cyberduck; select ‘Go’ -> ‘open in terminal’ from the menu.

Command Description
apropos whatis Show commands pertinent to string. See also threadsafe
man -t ascii | ps2pdf – > ascii.pdf make a pdf of a manual page
which command Show full path name of command
time command See how long a command takes
time cat Start stopwatch. Ctrl-d to stop. See also sw
dir navigation
cd - Go to previous directory
cd Go to $HOME directory
(cd dir && command) Go to dir, execute command and return to current dir
pushd . Put current dir on stack so you can popd back to it
alias l=’ls -l –color=auto’ quick dir listing
ls -lrt List files by date. See also newest and find_mm_yyyy
ls /usr/bin | pr -T9 -W$COLUMNS Print in 9 columns to width of terminal
find -name ‘*.[ch]‘ | xargs grep -E ‘expr’ Search ‘expr’ in this dir and below. See also findrepo
find -type f -print0 | xargs -r0 grep -F ‘example’ Search all regular files for ‘example’ in this dir and below
find -maxdepth 1 -type f | xargs grep -F ‘example’ Search all regular files for ‘example’ in this dir
find -maxdepth 1 -type d | while read dir; do echo $dir; echo cmd2; done Process each item with multiple commands (in while loop)
find -type f ! -perm -444 Find files not readable by all (useful for web site)
find -type d ! -perm -111 Find dirs not accessible by all (useful for web site)
locate -r ‘file[^/]*\.txt’ Search cached index for names. This re is like glob *file*.txt
look reference Quickly search (sorted) dictionary for prefix
grep –color reference /usr/share/dict/words Highlight occurances of regular expression in dictionary
archives and compression
gpg -c file Encrypt file
gpg file.gpg Decrypt file
tar -c dir/ | bzip2 > dir.tar.bz2 Make compressed archive of dir/
bzip2 -dc dir.tar.bz2 | tar -x Extract archive (use gzip instead of bzip2 for tar.gz files)
tar -c dir/ | gzip | gpg -c | ssh user@remote ‘dd of=dir.tar.gz.gpg’ Make encrypted archive of dir/ on remote machine
find dir/ -name ‘*.txt’ | tar -c –files-from=- | bzip2 > dir_txt.tar.bz2 Make archive of subset of dir/ and below
find dir/ -name ‘*.txt’ | xargs cp -a –target-directory=dir_txt/ –parents Make copy of subset of dir/ and below
( tar -c /dir/to/copy ) | ( cd /where/to/ && tar -x -p ) Copy (with permissions) copy/ dir to /where/to/ dir
( cd /dir/to/copy && tar -c . ) | ( cd /where/to/ && tar -x -p ) Copy (with permissions) contents of copy/ dir to /where/to/
( tar -c /dir/to/copy ) | ssh -C user@remote ‘cd /where/to/ && tar -x -p’ Copy (with permissions) copy/ dir to remote:/where/to/ dir
dd bs=1M if=/dev/sda | gzip | ssh user@remote ‘dd of=sda.gz’ Backup harddisk to remote machine
rsync (Network efficient file copier: Use the –dry-run option for testing)
rsync -P rsync://rsync.server.com/path/to/file file Only get diffs. Do multiple times for troublesome downloads
rsync –bwlimit=1000 fromfile tofile Locally copy with rate limit. It’s like nice for I/O
rsync -az -e ssh –delete ~/public_html/ remote.com:’~/public_html’ Mirror web site (using compression and encryption)
rsync -auz -e ssh remote:/dir/ . && rsync -auz -e ssh . remote:/dir/ Synchronize current directory with remote one
ssh (Secure SHell)
ssh $USER@$HOST command Run command on $HOST as $USER (default command=shell)
ssh -f -Y $USER@$HOSTNAME xeyes Run GUI command on $HOSTNAME as $USER
scp -p -r $USER@$HOST: file dir/ Copy with permissions to $USER’s home directory on $HOST
scp -c arcfour $USER@$LANHOST: bigfile Use faster crypto for local LAN. This might saturate GigE
ssh -g -L 8080:localhost:80 root@$HOST Forward connections to $HOSTNAME:8080 out to $HOST:80
ssh -R 1434:imap:143 root@$HOST Forward connections from $HOST:1434 in to imap:143
ssh-copy-id $USER@$HOST Install public key for $USER@$HOST for password-less log in
wget (multi purpose download tool)
(cd dir/ && wget -nd -pHEKk http://www.pixelbeat.org/cmdline.html) Store local browsable version of a page to the current dir
wget -c http://www.example.com/large.file Continue downloading a partially downloaded file
wget -r -nd -np -l1 -A ‘*.jpg’ http://www.example.com/dir/ Download a set of files to the current directory
wget ftp://remote/file[1-9].iso/ FTP supports globbing directly
wget -q -O- http://www.pixelbeat.org/timeline.html | grep ‘a href’ | head Process output directly
echo ‘wget url’ | at 01:00 Download url at 1AM to current dir
wget –limit-rate=20k url Do a low priority download (limit to 20KB/s in this case)
wget -nv –spider –force-html -i bookmarks.html Check links in a file
wget –mirror http://www.example.com/ Efficiently update a local copy of a site (handy from cron)
networking (Note ifconfig, route, mii-tool, nslookup commands are obsolete)
ethtool eth0 Show status of ethernet interface eth0
ethtool –change eth0 autoneg off speed 100 duplex full Manually set ethernet interface speed
iwconfig eth1 Show status of wireless interface eth1
iwconfig eth1 rate 1Mb/s fixed Manually set wireless interface speed
iwlist scan List wireless networks in range
ip link show List network interfaces
ip link set dev eth0 name wan Rename interface eth0 to wan
ip link set dev eth0 up Bring interface eth0 up (or down)
ip addr show List addresses for interfaces
ip addr add 1.2.3.4/24 brd + dev eth0 Add (or del) ip and mask (255.255.255.0)
ip route show List routing table
ip route add default via 1.2.3.254 Set default gateway to 1.2.3.254
host pixelbeat.org Lookup DNS ip address for name or vice versa
hostname -i Lookup local ip address (equivalent to host `hostname`)
whois pixelbeat.org Lookup whois info for hostname or ip address
netstat -tupl List internet services on a system
netstat -tup List active connections to/from system
windows networking (Note samba is the package that provides all this windows specific networking support)
smbtree Find windows machines. See also findsmb
nmblookup -A 1.2.3.4 Find the windows (netbios) name associated with ip address
smbclient -L windows_box List shares on windows machine or samba server
mount -t smbfs -o fmask=666,guest //windows_box/share /mnt/share Mount a windows share
echo ‘message’ | smbclient -M windows_box Send popup to windows machine (off by default in XP sp2)
text manipulation (Note sed uses stdin and stdout. Newer versions support inplace editing with the -i option)
sed ‘s/string1/string2/g’ Replace string1 with string2
sed ‘s/\(.*\)1/\12/g’ Modify anystring1 to anystring2
sed ‘/ *#/d; /^ *$/d’ Remove comments and blank lines
sed ‘:a; /\\$/N; s/\\\n//; ta’ Concatenate lines with trailing \
sed ‘s/[ \t]*$//’ Remove trailing spaces from lines
sed ‘s/\([`"$\]\)/\\\1/g’ Escape shell metacharacters active within double quotes
seq 10 | sed “s/^/ /; s/ *\(.\{7,\}\)/\1/” Right align numbers
sed -n ’1000{p;q}’ Print 1000th line
sed -n ’10,20p;20q‘ Print lines 10 to 20
sed -n ‘s/.*<title>\(.*\)<\/title>.*/\1/ip;T;q‘ Extract title from HTML web page
sed -i 42d ~/.ssh/known_hosts Delete a particular line
sort -t. -k1,1n -k2,2n -k3,3n -k4,4n Sort IPV4 ip addresses
echo ‘Test’ | tr ‘[:lower:]‘ ‘[:upper:]‘ Case conversion
tr -dc ‘[:print:]‘ < /dev/urandom Filter non printable characters
tr -s ‘[:blank:]‘ ‘\t’ </proc/diskstats | cut -f4 cut fields separated by blanks
history | wc -l Count lines
set operations (Note you can export LANG=C for speed. Also these assume no duplicate lines within a file)
sort file1 file2 | uniq Union of unsorted files
sort file1 file2 | uniq -d Intersection of unsorted files
sort file1 file1 file2 | uniq -u Difference of unsorted files
sort file1 file2 | uniq -u Symmetric Difference of unsorted files
join -t’\0′ -a1 -a2 file1 file2 Union of sorted files
join -t’\0′ file1 file2 Intersection of sorted files
join -t’\0′ -v2 file1 file2 Difference of sorted files
join -t’\0′ -v1 -v2 file1 file2 Symmetric Difference of sorted files
math
echo ‘(1 + sqrt(5))/2′ | bc -l Quick math (Calculate ?). See also bc
seq -f ’4/%g’ 1 2 99999 | paste -sd-+ | bc -l Calculate ? the unix way
echo ‘pad=20; min=64; (100*10^6)/((pad+min)*8)’ | bc More complex (int) e.g. This shows max FastE packet rate
echo ‘pad=20; min=64; print (100E6)/((pad+min)*8)’ | python Python handles scientific notation
echo ‘pad=20; plot [64:1518] (100*10**6)/((pad+x)*8)’ | gnuplot -persist Plot FastE packet rate vs packet size
echo ‘obase=16; ibase=10; 64206′ | bc Base conversion (decimal to hexadecimal)
echo $((0x2dec)) Base conversion (hex to dec) ((shell arithmetic expansion))
units -t ’100m/9.58s’ ‘miles/hour’ Unit conversion (metric to imperial)
units -t ’500GB’ ‘GiB’ Unit conversion (SI to IEC prefixes)
units -t ’1 googol’ Definition lookup
seq 100 | (tr ‘\n’ +; echo 0) | bc Add a column of numbers. See also add and funcpy
calendar
cal -3 Display a calendar
cal 9 1752 Display a calendar for a particular month year
date -d fri What date is it this friday. See also day
[ $(date -d "tomorrow" +%d) = "01" ] || exit exit a script unless it’s the last day of the month
date –date=’25 Dec’ +%A What day does xmas fall on, this year
date –date=’@2147483647′ Convert seconds since the epoch (1970-01-01 UTC) to date
TZ=’America/Los_Angeles’ date What time is it on west coast of US (use tzselect to find TZ)
date –date=’TZ=”America/Los_Angeles” 09:00 next Fri’ What’s the local time for 9AM next Friday on west coast US
locales
printf “%’d\n” 1234 Print number with thousands grouping appropriate to locale
BLOCK_SIZE=\’1 ls -l Use locale thousands grouping in ls. See also l
echo “I live in `locale territory`” Extract info from locale database
LANG=en_IE.utf8 locale int_prefix Lookup locale info for specific country. See also ccodes
locale -kc $(locale | sed -n ‘s/\(LC_.\{4,\}\)=.*/\1/p’) | less List fields available in locale database
recode (Obsoletes iconv, dos2unix, unix2dos)
recode -l | less Show available conversions (aliases on each line)
recode windows-1252.. file_to_change.txt Windows “ansi” to local charset (auto does CRLF conversion)
recode utf-8/CRLF.. file_to_change.txt Windows utf8 to local charset
recode iso-8859-15..utf8 file_to_change.txt Latin9 (western europe) to utf8
recode ../b64 < file.txt > file.b64 Base64 encode
recode /qp.. < file.qp > file.txt Quoted printable decode
recode ..HTML < file.txt > file.html Text to HTML
recode -lf windows-1252 | grep euro Lookup table of characters
echo -n 0×80 | recode latin-9/x1..dump Show what a code represents in latin-9 charmap
echo -n 0x20AC | recode ucs-2/x2..latin-9/x Show latin-9 encoding
echo -n 0x20AC | recode ucs-2/x2..utf-8/x Show utf-8 encoding
CDs
gzip < /dev/cdrom > cdrom.iso.gz Save copy of data cdrom
mkisofs -V LABEL -r dir | gzip > cdrom.iso.gz Create cdrom image from contents of dir
mount -o loop cdrom.iso /mnt/dir Mount the cdrom image at /mnt/dir (read only)
cdrecord -v dev=/dev/cdrom blank=fast Clear a CDRW
gzip -dc cdrom.iso.gz | cdrecord -v dev=/dev/cdrom - Burn cdrom image (use dev=ATAPI -scanbus to confirm dev)
cdparanoia -B Rip audio tracks from CD to wav files in current dir
cdrecord -v dev=/dev/cdrom -audio -pad *.wav Make audio CD from all wavs in current dir (see also cdrdao)
oggenc –tracknum=’track’ track.cdda.wav -o ‘track.ogg’ Make ogg file from wav file
disk space (See also FSlint)
ls -lSr Show files by size, biggest last
du -s * | sort -k1,1rn | head Show top disk users in current dir. See also dutop
du -hs /home/* | sort -k1,1h Sort paths by easy to interpret disk usage
df -h Show free space on mounted filesystems
df -i Show free inodes on mounted filesystems
fdisk -l Show disks partitions sizes and types (run as root)
rpm -q -a –qf ‘%10{SIZE}\t%{NAME}\n’ | sort -k1,1n List all packages by installed size (Bytes) on rpm distros
dpkg-query -W -f=’${Installed-Size;10}\t${Package}\n’ | sort -k1,1n List all packages by installed size (KBytes) on deb distros
dd bs=1 seek=2TB if=/dev/null of=ext3.test Create a large test file (taking no space). See also truncate
> file truncate data of file or create an empty file
monitoring/debugging
tail -f /var/log/messages Monitor messages in a log file
strace -c ls >/dev/null Summarise/profile system calls made by command
strace -f -e open ls >/dev/null List system calls made by command
strace -f -e trace=write -e write=1,2 ls >/dev/null Monitor what’s written to stdout and stderr
ltrace -f -e getenv ls >/dev/null List library calls made by command
lsof -p $$ List paths that process id has open
lsof ~ List processes that have specified path open
tcpdump not port 22 Show network traffic except ssh. See also tcpdump_not_me
ps -e -o pid,args –forest List processes in a hierarchy
ps -e -o pcpu,cpu,nice,state,cputime,args –sort pcpu | sed ‘/^ 0.0 /d’ List processes by % cpu usage
ps -e -orss=,args= | sort -b -k1,1n | pr -TW$COLUMNS List processes by mem (KB) usage. See also ps_mem.py
ps -C firefox-bin -L -o pid,tid,pcpu,state List all threads for a particular process
ps -p 1,$$ -o etime= List elapsed wall time for particular process IDs
last reboot Show system reboot history
free -m Show amount of (remaining) RAM (-m displays in MB)
watch -n.1 ‘cat /proc/interrupts’ Watch changeable data continuously
udevadm monitor Monitor udev events to help configure rules
system information (see also sysinfo) (‘#’ means root access is required)
uname -a Show kernel version and system architecture
head -n1 /etc/issue Show name and version of distribution
cat /proc/partitions Show all partitions registered on the system
grep MemTotal /proc/meminfo Show RAM total seen by the system
grep “model name” /proc/cpuinfo Show CPU(s) info
lspci -tv Show PCI info
lsusb -tv Show USB info
mount | column -t List mounted filesystems on the system (and align output)
grep -F capacity: /proc/acpi/battery/BAT0/info Show state of cells in laptop battery
dmidecode -q | less Display SMBIOS/DMI information
smartctl -A /dev/sda | grep Power_On_Hours How long has this disk (system) been powered on in total
hdparm -i /dev/sda Show info about disk sda
hdparm -tT /dev/sda Do a read speed test on disk sda
badblocks -s /dev/sda Test for unreadable blocks on disk sda
interactive
readline Line editor used by bash, python, bc, gnuplot, …
screen Virtual terminals with detach capability, …
mc Powerful file manager that can browse rpm, tar, ftp, ssh, …
gnuplot Interactive/scriptable graphing
links Web browser
xdg-open . open a file or url with the registered desktop application
]]> http://www.i-net.com.au/2011/04/03/linux-cheat-sheet/feed/ 0 Bulutroofing.com.au http://www.i-net.com.au/2011/03/07/bulutroofing-com-au/ http://www.i-net.com.au/2011/03/07/bulutroofing-com-au/#comments Mon, 07 Mar 2011 06:11:06 +0000 admin http://www.i-net.com.au/?p=1329
&h=126&w=106&zc=1″ />
Bill of Internetwork Solutions is the ideal website designer, particularly for those who are starting from scratch. He has a vast knowledge and experience, and communicates this with clarity and great patience. I was delighted with my website, and it has received many compliments from my business associates and clients.

- Bekir, Bulut Roofing

]]> http://www.i-net.com.au/2011/03/07/bulutroofing-com-au/feed/ 0 cpcgroup.com.au http://www.i-net.com.au/2011/03/07/cpcgroup-com-au/ http://www.i-net.com.au/2011/03/07/cpcgroup-com-au/#comments Mon, 07 Mar 2011 05:07:01 +0000 admin http://www.i-net.com.au/?p=1325

I would formally like to thank you for your work that you have done for my company’s website, staff and clients are highly impressed by the standard of professionalism in the design and quality of your work.
On behalf of CPC Group we would like to thank you for your hard work as well as recommend your services to any potential client.

- Rozetta, cpcgroup.com.au

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