Location

/var/log

Or 

/var/logs

Other Methods

 sudo tail -f /var/log/syslog

 sudo less -f /var/log/syslog

sudo more -f /var/log/syslog

sudo cat /var/log/syslog

For passwordless login, hit enter when asked for password then hit enter again for default name.

mkdir .ssh #not needed in most cases
ssh-keygen -t rsa -b 4096
Or just ssh-keygen -t rsa

ssh-copy-id -i .ssh/id_rsa.pub username@otherserver

If on an alternative port other than default 22

  ssh-copy-id -i .ssh/id_rsa.pub "user@other-server.com" -p45343

This will delete the content of the specified folder without deleting folders, just files.

find /var/Vol1/* -mtime +29 -exec rm -f {} \;

cd /home/

find . -depth -print0 | cpio --null --sparse -pvd /backup/home/

This works well on Centos

//192.168.1.50/temperature /var/www/html/hot  cifs password=ASF1f02@2,username=KoocooMonster

This works for Ubuntu

//192.168.1.50/apps  /media/192.168.1.50 cifs workgroup=NDS2K,password=ASF1f02@2,username=KoocooMonster 0  0

To split

split /media/storage1/Largefile.zip /media/APPS2/slize/export.1

To join

cat export.1* > NEWFILENAME

Assuming that you have a directory /logs

This is the actual command that runs on one of my  cron jobs.

logwatch --detail=High --range=Today >/logs/watchdog.txt  && mv /logs/watchdog.txt /logs/"´date +%Y-%m-%d_%H´.txt" 

To rename a file

mv /logs/watchdog.txt /logs/"´date +%Y-%m-%d_%H´.txt" 

OR

dt=$( date +%Y%M%d ) && cp /var/Vol1/backup/pdf_form /var/Vol1/backup/"$dt"_pdf_form ;

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages. Squid has extensive access controls and makes a great server accelerator. It runs on most available operating systems, including Windows and is licensed under the GNU GPL.
Thanks to Jayson for this guide

Complete Steps in Setting up UBUNTU Server 10 with SQUID 3 as a Transparent Proxy.

Step 1. Install the Ubuntu Server 10, include LAMP if you want

Step 2. Change the network interfaces from dhcp to static

sudo nano /etc/network/interfaces

auto eth0
iface eth0 inet static
address 192.168.1.250
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.88

post-up iptables-restore < /etc/iptables.up.rules

auto eth1
iface eth1 inet static
address 192.168.2.1
netmask 255.255.255.0
network 192.168.2.0
broadcast 192.168.2.255

Step 3. Install Web Admin (webmin) (Optional)

wget http://prdownloads.sourceforge.net/webadmin/webmin_1.510-2_all.deb
dpkg –install webmin_1.510-2_all.deb
sudo apt-get -f install

https://localhost-IP ADDRES:10000

*Note Make sure you give permission to the IPTABLES ruleset to for you to access webmin over the net.

Step 4. Install ClamAV and ClamAV-freshclam

sudo apt-get install clamav clamav-freshclam

Step 5. The first step is to install squid 3

sudo apt-get install squid3

edit the squid 3 configuration file in your favorite editor

sudo nano /etc/squid3/squid.conf

and set the transparency and the allowed hosts

http_port 3128 transparent
acl our_networks src 192.168.2.0/24
acl localnet src 127.0.0.1/255.255.255.255
http_access allow our_networks
http_access allow localnet

where 192.168.2.0/24 is the IP range of local network. Probably you need to adjust the swap size

cache_dir ufs /var/spool/squid3 7000 16 256

here the first number denotes the size of cache in megabytes. Save you changes and restart the squid proxy by

sudo /etc/init.d/squid3 restart

Step 6. Edit the /etc/sysctl.conf

sudo nano /etc/sysctl.conf

Uncomment the line that enable packet forwarding for IPv4 and IPv6

Net.ipv4.ip_forward = 1
Net.ipv6.conf.all.forwarding = 1

Step 7. Edit the IPTABLE ruleset of NAT and FILTER

sudo nano /etc/iptables.up.rules

*nat

-A PREROUTING –i eth1 –p tcp –m tcp –dport 80 –j DNAT –to-destination 192.168.2.1:3128
-A PREROUTING –i eth1 –p tcp –m tcp –dport 80 –j REDIRECT –to-ports 3128
-A POSTROUTING –s 192.168.2.0/24 –o eth0 –j MASQUERADE

*filter

-A INPUT –i lo –j ACCEPT
-A INPUT –m state –i eth0 –state REALATED,ESTABLISHED –j ACCEPT
-A INPUT eth1 –j ACCEPT
-A INPUT –p tcp –m tcp –dport 22 –j ACCEPT # permit ssh using putty
-A INPUT –p tcp –m tcp –dport 10000 –j ACCEPT # permit webmin access
-A INPUT –j LOG
-A INPUT –j DROP
-A FORWARD –i eth1 –j ACCEPT
-A OUTPUT –o lo –j ACCEPT
-A OUTPUT –o eth1 –j ACCEPT
-A FOWARD –o eth1 –j ACCEPT
-A FORWARD –s 192.168.2.0/24 –o eth0 –j ACCEPT
-A FORWARD –d 192.168.2.0/24 –m state –state ESTABLISHED,REALTED –I eth0 –j ACCEPT

STEP 8. Edit rc.local

sudo nano /etc/rc.local

iptables -t nat -A POSTROUTING -s 192.168.2.0/24 –o eth0 -j MASQUERADE

Step 9. reboot the server

Step 10. Configure the workstation for static IP Address making the LAN IP of the Ubuntu box as the gateway. Make sure that the IP Address of the workstation is within the network you setup.

Extracted from http://www.ubuntugeek.com/setting-up-ubuntu-10-04-lucid-server-with-squid-3-as-a-transparent-proxy.html

Edit 'main.cf' file, create/edit a line as follows:

Centos and Ubuntu location /etc/postfix/main.cf

relayhost = smtp.west.cox.net

 This is helpful to see the type of memory you need to purchase, in case of upgrades or replacements.

sudo dmidecode --type 17

# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 2.6 present.

Handle 0x0034, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 16384 MB
Form Factor: DIMM
Set: None
Locator: DIMM1_CPU1
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Samsung-00CE
Serial Number: 122AD394
Asset Tag: 031443
Part Number: M393B2G70QH0-CMA
Rank: 2

Handle 0x0036, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM3_CPU1
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 364997DC
Asset Tag: 011211
Part Number: HMT325R7CFR8C-PB
Rank: 1

Handle 0x0038, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 8192 MB
Form Factor: DIMM
Set: None
Locator: DIMM2_CPU1
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 429962C5
Asset Tag: 011218
Part Number: HMT31GR7CFR4C-PB
Rank: 2

Handle 0x003A, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM4_CPU1
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 365997F5
Asset Tag: 011211
Part Number: HMT325R7CFR8C-PB
Rank: 1

Handle 0x003C, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 8192 MB
Form Factor: DIMM
Set: None
Locator: DIMM1_CPU2
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 2C30AD87
Asset Tag: 011232
Part Number: HMT31GR7CFR4C-PB
Rank: 2

Handle 0x003E, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM3_CPU2
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 367997F5
Asset Tag: 011211
Part Number: HMT325R7CFR8C-PB
Rank: 1

Handle 0x0040, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 16384 MB
Form Factor: DIMM
Set: None
Locator: DIMM2_CPU2
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Samsung-00CE
Serial Number: 122AD346
Asset Tag: 031443
Part Number: M393B2G70QH0-CMA
Rank: 2

Handle 0x0042, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM4_CPU2
Bank Locator: Not Specified
Type: DDR3
Type Detail: Registered (Buffered)
Speed: 1067 MHz
Manufacturer: Hyundai-00AD
Serial Number: 367997DD
Asset Tag: 011211
Part Number: HMT325R7CFR8C-PB
Rank: 1

1. Dial ****73738#
2. Dial 1# to confirm

From the Phone dial ****  then press 110#   - this will say the current IP

Run this and  select the lowest ping 

ping proxy.lax.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.dca.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.mia.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.atl.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.chi.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.bos.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.nyc.broadvoice.com -i 3 -c3 >>ping.txt && cat ping.txt

-----------

Run this and  select the lowest ping 

ping proxy.lax.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.dca.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.mia.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.atl.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.chi.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.bos.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.nyc.broadvoice.com -i 3 -c3 >>ping.txt && cat ping.txt

-----------

sudo dmidecode

sudo biosdecode

sudo apt install sipsak

$ sipsak -vv -s sip:2444@yourvoip.server.com

Source https://sourceforge.net/projects/sipsak.berlios/

Very simple:

sudo ap-get install tsocks -y

Once installed, edit config file

nano /etc/tsocks.conf

Go all the way down and replace, server with your loopback IP and server port, to whatever you want as long as it not being used by other apps.

server = 127.0.0.1

# The port defaults to 1080 

#Change port as needed
server_port = 1098

Now to connect from another location

ssh -D 1098 yourusername@yourTsocksMachine.com -p22 ;

Note: you don't need to change or add any forwarding to port 1098 from the router, you only need to forward port 22 or whatever you use for SSH to that machine.

Once you have successfully connected, open a new terminal (Don't use the same) and type:

tsocks firefox

or try any other browser or compatible app.

such as 

tsocks midori

tsocks google-chrome

tsocks thunderbird

tsocks filezilla

Make sure these apps are not already open, for example for my local browsing I use chrome, and for my tsocks connections I use firefox or midory, you can create independent links to these apps so you know where you are connecting to.

To get info such as, speed, quality, etc.

iwconfig

iwconfig wlan0

iwconfig wlan0 | egrep -e "Quality" -e "Rate"

<!-- @page { margin: 0.79in } P { margin-bottom: 0.08in } -->

wlan0 IEEE 802.11abgn ESSID:"It-Hertz-When-IP"

Mode:Managed Frequency:2.437 GHz Access Point: 00:24:B2:71:CB:EC

Bit Rate=54 Mb/s Tx-Power=14 dBm

Retry long limit:7 RTS thr:off Fragment thr:off

Power Management:off

Link Quality=59/70 Signal level=-51 dBm

Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0

Tx excessive retries:0 Invalid misc:58 Missed beacon:0

Rsync I use this alot to synchronize several machines, 

A basic way 

To limit the Bandwidth  

rsync -rtvaz --delete --bwlimit=1000  -e 'ssh -p 22' lnxbox.yourdomain.com:/var/Vol1/MEDIA/  /Vol0/MEDIA

From your local machine to a machine with alternate SSH port, excluding folders complete and incomplete

rsync -e 'ssh -p 3426' -rtva /srv/storage/downloads/ root@remote.azt.com:/var/Vol1/TV/ --exclude 'complete' --exclude 'incomplete' --stats --progress

To sync specific type of files, on this case only MKV files

rsync -rtv -a --include '*/' --include '*.mkv' --exclude '*' /var/Vol1/MEDIA/ root@192.168.1.58:/var/Vol1/MEDIA/

disable UseDNS by editing /etc/ssh/sshd_config 
UseDNS no

VBoxHeadless -startvm servername 

Or

nohup vboxheadless -startvm Windows7 < /dev/null > /dev/null 2>&1 & 

 This is old, but still useful

df -h

umount /dev/mmcblk0p1

sudo dd bs=1M if=archlinuxarm-13-06-2012.img of=/dev/mmcblk0p1

Create a cron job 

cd /etc/init.d && motion start

Then create another one to kill it at determinated time.

killall motion &&

chmod 777 -R /var/Vol1/Motion/;

tcpdump -n "dst host 192.168.10.1 and dst port 5060" -vw /var/log/asterisk/capture.cap

Another way

tcpdump -n "port 5060" -vw sip.dump

From Ubuntu

sox sourceStereo.wav -r 8k -c 1 out-mono8kfile.wav

Most sites out there have multiple comments about so called freeware to open OST files, the fact is that most of them are nothing but scams to get you to purchase the real application, the easiest way to open a OST or PST file is with the email client Evolution, I don’t know if available for Windows but If you have a computer and a pendrive, just bootup a live Linux version that has Evolution included, do an Import –select Import a Single file and select the OST file, it will take a while to finish the import.

The reason I needed to open the file was to get the contacts from an old email address that was no longer available, nor I had access to the server.

 Perhaps too old, but could be useful

This was extracted from http://nerdvittles.com/?tag=piaf

MP3 Playback . Log into your server as root and issue the following commands. If you want to activate the transcription feature, edit the downloaded script and change transcribe=0 to transcribe=1.

cd /root
wget http://pbxinaflash.com/installmp3stt.sh
chmod +x installmp3stt.sh
./installmp3stt.sh


Once you have run the installation script, you’ll need to make a couple of adjustments in the FreePBX GUI. Log into FreePBX 2.11 and choose Settings, Voicemail Admin, Settings and make the following changes:

format: wav|wav49
mailcmd: /usr/sbin/sendmailmp3

This is very useful for automating tasks in remote machines or to gather remote info from many machines at once.

ssh root@192.168.1.48 'uptime'

For multiple commands

ssh root@192.168.1.48 'uptime ; df -h'

Works best with passwordless SSH

Something easy to use fswebcam

apt-get install fswebcam

fswebcam -r 1080x780 --jpeg 90 -D 1 snap.jpg

If you try to partition a large drive and get this error

sectors exceeds the msdos-partition-table-imposed maximum of ....

The solution is to partition using "gpt"

Using GParted:

 Device --> Create Partition Table and select "gpt"

After that, Format the drive with whatever you need, in my case I use several of these drives for rotational backups as external removable drives on windows systems, so I use NTFS, but if you are going to be using the drive for Linux, EXT4 is probably going to be your best choice.

First you need to install Iperf on all the machines that you wish to test throughput.

sudo apt-get install iperf

Once you have it installed, select a machine to be the server and run the following command

iperf -s or iperf --server

From the other computers run:

iperf -c 192.168.50.15 -f M

 More info https://iperf.fr/

cd into directory 

find . -depth -name '* *' \ | while IFS= read -r f ; do mv -i "$f" "$(dirname "$f")/$(basename "$f"|tr ' ' _)" ; done

Taken from Here, works great for Piwigo

To install Navit and GPSD 

sudo apt-get install navit gpsd gpsd-clients python-gps -y

Copy to your home directory

cp /etc/navit/navit.xml ~/.navit/navit.xml
cd /home/pi/.navit

Get a map (using your browser)

http://maps.navit-project.org  (zoom and select the desired area and hit download)

Rename the downloaded file to something like Phoenix.bin and place it under  

/home/pi/.navit/

Disable sample maps

CHANGE TO:
<!-- If you dont want to use the sample map, either set enabled="no" in the next line or remove the xml file from the maps directory -->
<mapset enabled="no">
<xi:include href="$NAVIT_SHAREDIR/maps/*.xml"/>
</mapset>

Enable your Map

<!-- Mapset template for openstreetmaps -->
<mapset enabled="yes">
<map type="binfile" enabled="yes" data="/home/pi/.navit/Phoenix.bin"/>
</mapset>

To get a USB GPS working 
Works for Navit and other GIS software, such as kismet and others.

sudo nano /etc/default/gpsd

START_DAEMON="true"
# Use USB hotplugging to add new USB devices automatically to the daemon
USBAUTO="true"
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyUSB0"
# Other options you want to pass to gpsd
GPSD_OPTIONS="/dev/ttyUSB0"
GPSD_SOCKET=”/var/run/gpsd.sock”

-------------------------------------------------------------------------------------------------------------------------------------------------- 

icacls "X:\apps\Test" /grant dom1\Standard_users:F

Most sites out there have multiple comments about so called freeware to open OST files, the fact is that most of them are nothing but scams to get you to purchase the real application, the easiest way to open a OST or PST file is with the email client Evolution, I don’t know if available for Windows but If you have a computer and a pendrive, just bootup a live Linux version that has Evolution included, do an Import –select Import a Single file and select the OST file, it will take a while to finish the import.

The reason I needed to open the file was to get the contacts from an old email address that was no longer available, nor I had access to the server.

Boot from XP CD - Select the repair option:

copy c:\windows\repair\system c:\windows\system32\config\system

It will require to reactivate windows  and most likely to install SP3

The following script will create a folder on the D: drive named as today's date in numeric format, this is great if you need to schedule your PC to run Backups on a specific time of the day and provide you with several versions of My Document folder, you could send them to your Dropbox folder, Mega, etc.

-----> Save the script bellow as MYDocs.bat and run it.

set myDate=%date:~4,2%%date:~7,2%%date:~10%

mkdir D:\%myDate%

robocopy "c:\users\%username%"\Documents\ D:\%myDate% /e /R:1 /v /np /eta /w:2 /PURGE /XD TEMP >c:\users\%username%"\Desktop\MYDocs.txt

curve

curve

This problem occurs sometimes when using robocopy , sometimes I Can't even see files in external drive and they are not hidden.

My solution is to run:

attrib -H -S /L  h:\folder

icacls "X:\apps\Test" /grant dom1\Standard_users:F

1. Dial ****73738#
2. Dial 1# to confirm

From the Phone dial ****  then press 110#   - this will say the current IP

Run this and  select the lowest ping 

ping proxy.lax.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.dca.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.mia.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.atl.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.chi.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.bos.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.nyc.broadvoice.com -i 3 -c3 >>ping.txt && cat ping.txt

-----------

Run this and  select the lowest ping 

ping proxy.lax.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.dca.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.mia.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.atl.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.chi.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.bos.broadvoice.com -i 3 -c3 >>ping.txt
ping proxy.nyc.broadvoice.com -i 3 -c3 >>ping.txt && cat ping.txt

-----------

sudo apt install sipsak

$ sipsak -vv -s sip:2444@yourvoip.server.com

Source https://sourceforge.net/projects/sipsak.berlios/

tcpdump -n "dst host 192.168.10.1 and dst port 5060" -vw /var/log/asterisk/capture.cap

Another way

tcpdump -n "port 5060" -vw sip.dump

From Ubuntu

sox sourceStereo.wav -r 8k -c 1 out-mono8kfile.wav

 Perhaps too old, but could be useful

This was extracted from http://nerdvittles.com/?tag=piaf

MP3 Playback . Log into your server as root and issue the following commands. If you want to activate the transcription feature, edit the downloaded script and change transcribe=0 to transcribe=1.

cd /root
wget http://pbxinaflash.com/installmp3stt.sh
chmod +x installmp3stt.sh
./installmp3stt.sh


Once you have run the installation script, you’ll need to make a couple of adjustments in the FreePBX GUI. Log into FreePBX 2.11 and choose Settings, Voicemail Admin, Settings and make the following changes:

format: wav|wav49
mailcmd: /usr/sbin/sendmailmp3