Linux   Linux – Create multiboot CD combining multiple ISO images



This post shows the steps to create a multiboot cd with multiple Linux distributions or tools.

For example, I created a recovery / disaster case cd with the following tools:
Clonezilla (to clone/recover disks and partitions)
Gparted (partition editior with GUI)
Trinity Rescue Kit (linux distribution for recovery and repair operations on Windows machines)

The Multicd Read more

Raspberry icon   Rasbperry – NO-IP configuration to be ran at boot time



If you need to update automatically a DNS entry with your public IP address (for example, to allow remote access to your home Raspberry or Linux), you can use the no-ip provider and its Linux or Raspberry client.

This posts shows the way to install the client and how to configure it to be started at boot time.

Register at

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Security   Security – Convert PFX to PEM using Windows or Linux



For certain application, a job partner asked me to send him certain certificate with private key in PEM format. Normally I’m using PFX format, but with a little help of the openssl toolkit converting PFX to PEM is quite easy.

Windows

openssl for windows can be downloaded here: http://gnuwin32.sourceforge.net/packages/openssl.htm
After extracting the contents, inside the bin subfolder the openssl … Read more

Linux   Linux – Running top command remotely (SSH)



Maybe you have tried to execute the top command to monitor processes on a remote host.

Error remotely – Run it in batch mode

If so, the following error can be returned:

$ ssh user@remotehost top -n1
TERM environment variable not set.

top does not work remotely in the default “interactive” mode. Use the “-b” parameter to run it in Read more

Icinga icon   Icinga – Installation / Setup on Debian Linux (1)



As you can see in previous posts…, Im in love with Nagios to monitor my systems… after creating some powerful, customized plugins for my Checkpoint firewalls, Exchange servers… cannot live with it… but maybe, it's "a bit" old fashioned and I have decided to try the Icinga monitoring tool. If it fits my environment, I'll have to replace my old … Read more

IRONPORT icon   Ironport – Automate commands / scripts from Linux



In a previous post (Linux: SSH connection without password (RSA public-key) I showed the way to configure a non-interactive SSH connection from-to a Linux system.

If the target system is a Ironport ESA device, the configuration is almost the same (generation of the key pair and configuration of the private one). But to install the new public key on … Read more

Linux   Linux – Create custom inetd service



The inetd (also known as superserver) is a daemon that provides (commonly on Linux and Unix systems) internet services. The configuration file inetd.conf contains the list of the offered services by the daemon. The clients connect to certain port and inetd launches the corresponding program to process the connection.

This example shows how to setup a service that executes remote … Read more

Linux   Mounting windows shares (CIFS-SMB) via fstab



Simple CIFS fstab entry

# cat /etc/fstab | grep SHARE
//FILESERVER/SHARE$       /mnt/SHARE     cifs   username=domain\user,password=mypassword 0 0

# mount /mnt/SHARE
# ls -ld /mnt/SHARE/
drwxrwxrwx 1 root root 4096 2014-07-01 08:34 /mnt/SHARE/

 

Avoid saving plain text password in /etc/fstab

# cat /etc/fstab | grep SHARE
//FILESERVER/SHARE$       /mnt/SHARE     cifs    credentials=/root/.smbcredentials 0 0

# cat /root/.smbcredentials
username=domain\user
password=mypassword

Dont forget .smbcredentials permissions

# 
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Linux   Linux – Bash scripting useful commands and tips



Some examples of very simple commands and features that become very powerful when used together. In future posts we'll see real examples of bash scripts used to create custom nagios checks/plugins.

Concatenate files – cat

# cat FILE1
this is the file1

# cat FILE2
this is the file2

# cat FILE1 FILE2
this is the file1
this is the 
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