How to Recover Data from Network Drives, Video Recorders and Linux Servers

To start a recovery mode in Linux:

• Restart the computer.
• While the computer is booting, press or hold a special key that opens the boot menu (for example: Esc, Shift, F8, F12 or Del).
• Select the recovery option or rescue mode.
• Wait until it boots.
• After booting in the recovery mode you will get access to basic utilities and command prompt that will allow you to run diagnostics, file recovery or system recovery operations if necessary.

To check the network drive (NAS) condition in Linux, several tools and commands can be used:

• Ping: to check availability of the network drive you can use the ping command.

For example:

ping (IP_address_of_the_network_drive)

• Nmap: to scan the network and find out which ports are open on a network device.

For example:

nmap (IP_address_of_the_network_drive)

• SSH or Telnet: If SSH or Telnet are enabled for this network drive, you can try connecting to it with these protocols to check its availability and system condition.
• Web interface: Many network drives offer a web interface for management and monitoring purposes. Typically, a web interface is available at the address http://(IP_address_of_the_network_drive) or https://(IP_address_of_the_network_drive).
• Commands for system monitoring: If you have access to your network drive via SSH or Telnet, you can use standard monitoring commands such as df to check the amount of free disk space, or top to view resource usage.

To monitor video recorder operation in Linux, you can use various tools that let you check the status of the whole system, its network and specific apps.

Here are some useful tools:

• top: The top command displays current system activity as well as the usage of CPU, memory and other resources. This lets you track the processes with high resource consumption, including processes related to the operation of a video recorder.
• htop: An improved version of the top command that features a more convenient interface that allows easy resource usage monitoring and process management.
• iotop: The tool to monitor disk activity that shows which processes are involved into input/output operations using the hard disk. It can be useful for monitoring the work of a video recorder writing video files to disks.
• nload: The tool to monitor network traffic in real time, displaying inbound and outbound traffic. It can be useful to check if the video recorder is sending or receiving data over the network.
• iftop: The tool to track network activity on the basis of IP addresses. It shows which connections are active and the amount of their traffic.
• netstat: The command to view active network connections and listening ports. It helps to find out if the video recorder establishes a network connection.
• log files: It is important to check journals (logs) of a video recorder to identify errors and issues. Standard system records can be viewed with the command journalctl.
• Monitoring scripts: You can create your own scripts in Bash or Python to monitor the video recorder’s condition automatically, to check its work, and to send error messages.

The main encryption methods in Linux:

• LUKS (Linux Unified Key Setup)
• eCryptfs (Enterprise Cryptographic Filesystem)
• EncFS
• GnuPG (GNU Privacy Guard)

The main factor affecting recovery of encrypted data is availability of corresponding encryption keys or passwords. Without these, data recovery is impossible.

There are a few programs that allow to recover deleted photos from cameras connected via USB to Linux. Here are some of them:

• PhotoRec
• Foremost
• Scalpel