Data Recovery and the Three Golden Backups

Our daily lives are tied to the digital world. Where once we had physical photos, CDs, books and files we now generate and buy the virtual equivalents. We store them on our electronic devices and assume that they will last forever in their digital homes, never needing to use data recovery to restore our virtual assets. But do they last forever?

Data Recovery when Computers Breakdown

A home computer can at any time be holding years of personal information and photos. Items that are irreplaceable to you. How long have you had your computer? The older a machine the greater the chance it will breakdown. When it does break you can feel you have lost part of who you are, this can be a scary time especially if you don’t have a backup. Try and stay calm and read this article from Cheeky Munkey about how to recover data from the hard drive within your computer.

data recovery needed

Avoid Hard Drive Data Recovery with Backups

Never get to the point where you need to recover lost files. Most companies that deal with data will have multiple copies of it. Three copies of any file is considered the minimum required. Just as the hip-hop group De La Soul thought that three was The Magic Number you can also use three as the magic number to prevent the need for data recovery.

  1. The original.
  2. A local copy on transportable media (e.g. USB drive, external hard drive).
  3. An off site copy (e.g. cloud storage or on media stored elsewhere, such as a family members house).

Backups are your files insurance policy for when your computer breaks down or is lost. The Internet has made preserving copies of files easier with services like Apple’s iCloud, Microsoft’s OneDrive, Google Drive and Dropbox where saving to a local folder automatically generates a remote copy. But don’t forget your own local copy on portable media. Ultimately the Internet is run by businesses and businesses have been known to shut off services. So remember your three golden backups for all your content.

Unzip File on VPS? How to Extract a Zip File on a Linux VPS

Tutorial to Upload and Extract a Zip File from Windows to a CentOS VPS

On Linux files are normally compressed individually to create a .gzip version using the gzip utility. Or several files are collected into a Tape Archive, .tar, which is an uncompressed collection of files created using the tar utility. A .tar is then compressed to a .gzip to create a .tar.gz. In Windows files are normally zipped, which is a format that collects and compresses several files into a single .zip file in a single operation.

When managing a Linux based Virtual Private Server (VPS) or other remote Linux machine, such as a web server, there can be occasions when a zip file created on Windows needs to be extracted and managed on the remote Linux machine. This can be done with the Linux zip (to compress) and unzip (to extract) utilities.

Install Zip and Unzip onto CentOS

Upload and unzip file on VPS (CentOS)A VPS may not run a full blown Linux, for example a CentOS VPS may run the minimal CentOS installation for efficiency. In which case the zip and unzip utilities may not be installed. These utilities can be installed on CentOS using yum:

Continue reading

Webmin CentOS Install for Easier VPS Management

Manage a CentOS VPS Using Webmin for System Administration

A Virtual Private Server (VPS) is a cost effective way to host web and cloud based solutions or high volume web sites. A VPS provides more resources (memory, processing power and disk space) than shared hosting without the cost of leasing dedicated hardware (although a VPS will not be as powerful as a dedicated machine). Some VPS packages only provide a minimal Linux system. Access to that minimal system is usually via a secure shell (SSH). Managing a Linux system remotely over SSH can be cumbersome. To make the system administration easier a web based management tool is useful. A commercial tool such as cPanel is often provided at extra cost. Open source alternatives like ZPanel and Webmin are available. In this tutorial article the Webmin system administration tool will be installed on a CentOS based VPS. CentOS, based on a Red Hat Linux distribution, is commonly available for VPS packages. This article assumes that the minimal installation of CentOS is used for the VPS operating system. The minimal CentOS does not have the desktop environment installed. The steps for the Webmin CentOS install are:

  1. Update CentOS using yum update.
  2. Add Webmin to the CentOS yum repositories.
  3. Add the Webmin package PGP key to the RPM keyring.
  4. Allow Webmin through the CentOS iptables firewall.
  5. Install Webmin using yum install webmin.
  6. Start Webmin and start using it.

Webmin Install Running on CentOS Continue reading

Change SSH Port from Default for CentOS Security Improvement

Help Harden a CentOS Server, Change SSH Port from Default Port Number 22

Edit the SSH configuration file to modify SSH port number. The configuration file is sshd_config. Adding Port XXXX where XXXX is the required port number. Then update SELinux and iptables. This is done to help harden CentOS against the less skilled hackers. The Secure Shell (SSH) is used to access a CentOS Server from another computer. For example when accessing a Virtual Private Server (VPS) to perform configuration changes. CentOS is a common option for a VPS operating system. This tutorial provides details on changing the SSH default port number for a CentOS server.

Steps to Change the CentOS SSH Port Number

The following steps are performed to change default SSH port number on CentOS:

  1. Login to the CentOS server.
  2. Back up then edit the /etc/ssh/sshd_config file.
  3. Add the line Port XXXX to the file, where XXXX is the new port number.
  4. Update the SELinux policy for the new SSH port.
  5. Update the iptables firewall rule for the new SSH port.
  6. Restart the services or the server.
  7. Check the changes worked by connecting on the new port.

Practice and Keep A Back Up

CentOS Logo

It is recommended to practice the instructions that follow on a local test environment before doing it on a live machine. This ensures familiarity with the process and reduces the risk of making mistakes on a live server. CentOS can be configured on a local Virtual Machine (VM) to practice these changes (see the Further Information section at the end of the article). For a remote VPS if you make a mistake reconfiguring the SSH port you may not be able to connect to it. It will require resetting via your service provider’s control panel. Always ensure you have a backup of any data that needs to be kept in the event the VPS needs to be reset. If SSH is the only option for configuration of a remote VPS consider other hardening options first, for example adding a sudo user for SSH login and removing the root user login over SSH. This article uses the shell (command line terminal) to change the CentOS configuration, based on a minimal CentOS install.

Edit the File sshd_config

To change the SSH port number edit the /etc/ssh/sshd_config file. Start by taking a copy in case anything goes wrong. For all commands in this article only enter the text after the # or $ prompt character, as seen on the terminal screen. Here’s the command to copy sshd_config to sshd_cfg_old:

# cp /etc/ssh/sshd_config /etc/ssh/sshd_cfg_old

Editing is done with vi or nano. On a minimal CentOS install, typical for a VPS, nano will not be installed by default. To edit sshd_config using vi:

# vi /etc/ssh/sshd_config

Or if logged in as a user with sudo ability:

$ sudo vi /etc/ssh/sshd_config

Add the Required Port Number

Select a new port number above 1024, one that is meaningful to you so it is remembered, or pick a random one. See List of TCP and UDP Port Numbers on Wikipedia. Some admins just double up port numbers, e.g. 22 becomes 2222, but that is familiar to hackers so pick something else, e.g. pick a memorable year and double it. For example 2×1066 is 2132, so port 2132 can be remembered as “Twice Battle of Hastings“.

The Port line should be in the first page of the file, as either Port 22 or commented out as #Port 22. Go to the line. Press Insert to enter edit mode. Remove the # if present and change the port number to the required value. Press the Esc key to return to command mode and enter :wq to write out the file and quit vi.

ssh_port_config

Update SELinux with the New Port Number

If the Security Enhanced Linux module (SELinux) is running then update selinux with the new port number. Failure to update SELinux for the new port will result in a Permission denied showing in the SELinux log.  To check that selinux is enabled run sestatus:

# sestatus
SELinux status: enabled
SELinuxfs mount: /selinux
Current mode: enforcing
Mode from config file: enforcing
Policy version: 24
Policy from config file: targeted

Use semanage to add the new port number to SELinux, see the article RHEL 6: semanage SELinux Command Not Found on how to install the command if not present (e.g. if using the CentOS minimal install). For this article this command was used to check the package for semanage:

# yum provides /usr/sbin/semange

And this command to install it:

# yum -y install policycoreutils-python

The port numbers for SELinux can be displayed using a semanage command (pipe to less to page through the list):

# semanage port -l | less

In the list of ports will be found ssh_port tcp 22. Use semanage to add the new port number:

# semanage port -a -t ssh_port_t -p tcp 2132

Update Firewall Rules for the New Port Number

The iptables firewall rules are listed using:

#iptables -L

There will be a rule showing that SSH is only allowed on port 22. This needs changing to the new port number. Use vi to open /etc/sysconfig/iptables:

# vi /etc/sysconfig/iptables

Go to this line:

-A INPUT -p tcp -m state –state NEW -m tcp –dport 22 -j ACCEPT

Change 22 after –dport to the new port number, e.g. 2132 (press Insert to enter edit mode in vi):

-A INPUT -p tcp -m state –state NEW -m tcp –dport 2132 -j ACCEPT

Save and exit (Esc key then :wq). Restart iptables:

# service iptables restart

Restart SSH

With the SSH config file changed, SELinux updated and iptables rules updated SSH can be restarted:

# /etc/init.d/sshd restart

Restarting CentOS

As an alternative to restarting iptables and ssh restart the the CentOS server:

# reboot

or

# shutdown -r now

Login to CentOS Using SSH to Test The New Port

On a Windows system a program such as PuTTY can be used to access a CentOS server using SSH. In this example the port number is 2132. To connect with the new port number enter it in the Port box.

PuTTY to SSH into different port

With the host name or IP address also entered select Open. The terminal prompt should appear allowing for a normal login.

(Note: If accessing a CentOS VPS on a VirtualBox virtual machine on the local computer you will need to change the Network Address Translation port from 22 to the new number, see the third article listed below.)

Further Information

Free Up Disk Space on Windows 8 with a Disk Cleanup

Disk Cleanup to Solve Low Disk Space Messages

Tips to free up disk space on Windows PCs, these disk cleanup pointers apply to the latest Windows versions, Windows 8.1, Windows 8 and Windows 7, also previous Windows versions, Windows Vista and Windows XP. With the use of Soild State Drives (SSDs) in new computers the amount of free disk space is generally lower than it used to be. This means that low disk space messages are more common. What types of messages will you see?

Low Disk Space and Similar Messages When The PC is Running

One day the PC is running OK, then out of the blue there are warning messages popping up. Sometimes these appear after installing a new program, or downloading a film from iTunes, or after a Windows Update. Sometimes the messages, or low disk space notifications, just start appearing for apparently no reason. Here are some of the typical messages that can be seen (and they usually come with a PC that starts running slower):

  • Low Disk Space.
  • Windows – Out of Virtual Memory.
  • Your system is low on virtual memory.
  • Your computer is low on memory.
  • Not enough storage is available to complete this operation.
  • There is not enough free disk space to run Steam.
  • There is not enough space to install these option(s).
  • There is not enough space on target drive while attempting to copy files.
  • There is not enough space on the disk.
  • There is not enough free disk space to extract the installation data.
  • There is not enough space on the Local Drive.
  • Close programs to prevent information loss.

What they generally mean (though not always) is that the PCs hard disk is nearly full up.If the hard disk gets completely full the computer will slow down and may not boot up correctly on next use. You may need to use a Windows boot disk or recovery disc to boot the system and free up some space.

Perform a Disk Cleanup to Free Up Disk Space

There are several disk cleanup task that can be performed. Once done the hard disk with be OK for a short while. However, a longer term solution will be required. Sometimes just reorganising the layout of the computers files will sort the issue. Sometimes it will be worth adding a new hard disk to reduce the problem in the future.

Accessing Control Panel in Windows 8.1 and Earlier Windows Versions

You will also need to access the computer’s Control Panel. On Windows 8 or Windows 8.1 at the Start screen start typing con and Control Panel will be listed for selection (or use the context menu, usually right click, on the Start flag and select Control Panel, alternatively hole the Windows key and press X then select Control Panel from the menu.) In Windows 7 and earlier access Control Panel via the Start button.

Use the Administrator Account for a Disk Cleanup

Let’s start the disk cleanup, You need to be logged on as a Computer Administrator to perform many of these cleanup tasks. If several users have accounts on the computer log in with one that is set up as a Computer Administrator (usually the first account created when the computer was first set up).

Empty the Recycle Bin

If there are items in the Recycle Bin on the desktop empty it. Look at the Recycle Bin icon on the desktop and if it looks like it has paper in it then it has items in it. Bring up Recycle Bin’s context menu (usually right-click) and select Empty Recycle Bin. A message may be displayed to confirm the permanent deletion. If required open the Recycle Bin (double-click) to check the contents.

Delete the Contents of the Windows Temporary Folder

Computer software, such as installers, apps and other programs will sometimes generate temporary files when running. Once the files are finished with they should be deleted by the software that generated them. Sometimes they don’t get deleted or the software crashes before the temporary files are deleted. If the software generated the files in the correct temporary location, either C:\Windows\Temp or in the logged on users AppData area (\AppData\Local\Temp), then these directories can be emptied.

(Sometimes the temporary directories are moved. To check their location view the systems environment variables. In Control Panel open System and Security select Advanced system settings. On the Advanced tab select Environment Variables. The location for temporary files is stored in the TEMP and TMP variables for the user and the system. TEMP and TMP normally point to the same place but can be set differently. User and system TEMP/TMP are normally different but again can be set to the same location.)

Close any running programs before cleaning the temporary directories. Using Windows File Explorer go to C:\Windows\Temp (or the location determined by the TEMP/TMP system environment variables). You may need to turn on Hidden items in Explorer using the View menu. Delete the all the contents of C:\Windows\Temp (you may need to give permission to do so). Some files and directories will not delete if programs or services are still using them.

Open the logged on users data folder. Either through C:\Users (e,g, C:\Users\John Doe for a user named John Doe) or the desktop with have a folder icon named after the user. Again with Hidden items enabled in Explorer browse to AppData\Local\Temp (or the location determined by the TEMP/TMP user environment variables). Delete all the contents. Again some may fail to delete because they are still in use.

If the computer has another hard disk with plenty of free space the TEMP and TMP directories can be changed to use the different disk. Change the TEMP/TMP user and system environment variables settings to a location on the other disk. E.g. create a TEMP directory on another hard disk, change the TEMP and TMP variables in Control Panel to point to the new directory. So if created on a D: drive it would be changed to D:\TEMP. Restart the computer for the change to take effect. Programs will use the new location for temporary files.

(Warning: A few programs will still use the default TEMP/TMP locations because of hard coded settings, including some Microsoft installers. So don’t forget to clear the C:\Windows\Temp and the user’s AppData\Local\Temp directories occasionally.)

Clear Web Caches and Move Them to Another Drive

For all the installed web browsers clear their caches. If the PC has another hard drive the cache locations can be moved to the other drive to help prevent low disk space issues in the future. The article Clear Web Cache and Moving Browser Cache Folder shows how to delete the web cache for Internet Explorer, Google Chrome, Mozilla Firefox and Opera.

Remove Unused Programs and Bloatware (Manufacturer Install Software)

Open Control Panel and under Programs select Uninstall Program. For each program no longer, or never, used select it and select Uninstall. Only remove programs you are sure about as some will be needed by the system and some used by other programs. Research the program on line if unsure. If in doubt leave it installed.

Turn Off Windows Features

Again using Programs in Control Panel select Turn Windows features on or off. Uncheck anything not used, however, it is likely that only advanced users will know what features can be turned off. Research on line if unsure and if in doubt don’t change the settings.

Delete Old Folders, Documents, Photos, Videos and Music

Using Windows Media Player, or your chosen media player (e.g. iTunes), to delete any media no longer required. Use Windows File Explorer to view the contents of the logged on users files. Delete any item (folders and files) no longer required.

Clear Out the Offline Email

If you email is stored on the computer and not the server then browse all the items and delete anything not required. Do this in the email program.

Remove Old Users and Their Files

You will need to be logged in as a Computer Administrator to delete other user accounts. Make sure any data stored under old user accounts is no longer required (if so copy it to another account or to offline storage).

In Control Panel under User Accounts and Family Safety select Add or remove user accounts. Select the account to remove. Click Delete the account. When asked if files should be kept select Delete Files to recover the space used by the account. Select Delete Account to confirm. The user account and all its files are removed.

Ensure Windows is Up To Date

Windows is updated regularly to improve security and reliability. This update process uses and creates temporary files. To delete these files first make sure all the latest updates have been installed. Otherwise updates that have been downloaded but not installed may be removed during the clean up process. (If this occurs they will be downloaded again at the next update.)

In Windows 7 use Windows Update via Start and All Programs. In Windows 8 type Settings at the Start screen and select PC Settings, then Update and Recovery. (Or in Control Panel enter Update in the search box and select Windows Update.)

Select Check for updates or Check now to ensure that “No updates are available”. Otherwise Install Updates. The Windows Update may fail if there is not enough space to install the update. Sometimes installing updates one-by-one (oldest first) can overcome update errors. Otherwise finish this list of disk cleanup tips and then try performing Windows Update again.

Run the Disk Cleanup Program

Free Disc Space Using Windows Disk Cleanup Advanced OptionsWindows comes with a Disk Cleanup utility that is automatically run once in a while. However, it can be run to clean up additional system files. Start Disk Cleanup by selecting it via Start, All Programs, Accessories and System Tools. On Window 8 type Disk at the Start screen and select the option that starts Clear Disk Space…

Note that when Disk Cleanup is performing the work it can take some time to complete. You may need to plan to leave it running for quite a while.

Select the drive to clean up, i.e. the one low on space. It will do a scan to determine files to cleanup. When the Disk Cleanup dialog displays select the Clean up system files button. Select the drive again and another scan is performed. Now a More Options tab is available. On the More Options tab select Clean up in the System Restore and Shadow Copies area. Confirm deletion of all but the last restore point by selecting Delete to the displayed question.

Click the OK button to perform the clean up of the items listed on the Disk Cleanup tab.

Sometimes the Disk Cleanup utility can appear to hang. It after a few hours it has not completed restart the computer. Continue with the remainder of these tips and return to Disk Cleanup after the other steps have been completed.

Run a Cleanup Utility

A dedicated third party cleaner, such as Piriform’s CCleaner (Computer Cleaner), will detect other files to clear. Running a utility like CCleaner can help remove unwanted files.

Clear the SoftwareDistribution Download Folder

If Windows Update is complete (see the Ensure Windows is Up to Date section earlier). Some of the files used by Windows Update but no longer required may still be left around. These can be removed to free up disk space. This is covered in the separate article SoftwareDistribution Folder Delete in Windows.

Clear the Prefetch Folder

Every time Windows starts, every time the same program is run, Windows loads the same program files again and again. Knowing this Windows bundles those files together in a cache called the Prefetch Folder. This folder is updated automatically by Windows. However, if disk space is really tight, and you have removed some recently used programs, you may free a little more space by deleting the contents of Prefetch. Windows will recreate the Pretch folder when the computer next runs. The small downside to deleting the contents of the Prefetch folder is that Windows start up and the running of some software will be slower than normal until the new Prefetch files have been automatically recreated.

To delete the contents of the Prefetch folder open up Windows Explorer, click on the Windows directory (normally C:\Windows). Find the Prefetch folder (C:\Windows\Prefetch). Select all the files in the folder (use Ctrl-A) and press delete. Restart the computer. (New prefetch files will be created as the computer is used). Windows automatically manages the Prefetch folder so clearing it is only required if disk space is extremely low.

Delete System Dump Files and Change the Creation Location

Windows can crash because of a hardware or software fault, or loss of power. When this happens Windows can create dump files that may be sent to Microsoft (to help diagnose faults). A dump file is literally a “dump” of the state of computer at the time of the crash. There can be a MEMORY.DMP file in C:\Windows and in C:\Windows\Minidump a series of dump files for each crash that occurs (if Windows got the chance to create the file). Note that depending upon dump settings and the nature of the crash either MEMORY.DMP or the mini-dump files may or may not be created.

If you do not need to analyse the cause of a crash the dump files can be deleted (if not already deleted by Disk Cleanup or a third party cleaning tool). Using Windows Explorer see if MEMORY.DMP is in C:\Windows and if so delete it. Go to C:\Windows\Minidump. and select all the files and press delete.

If required the location that the dump files are created can be changed. If space on the system disk is tight move the location to a disk that has more space. In fact MEMORY.DMP will not be created if the system disk is low on space. If this is the case and the PC is crashing often then change the dump file location. This will give the opportunity for analysis of the dump file at a later date.

Use Control Panel to open System and Security and select System. For the left hand list select Advanced system settings. On the Advanced tab under Start-up and Recovery select the Settings button. On the Start-up and Recovery dialog change the dump file location in the Write debugging information section. E.g. if a D:\TEMP directory existed on a machine (and the D: drive had lots of free space) the Kernel memory dump could be changed from %SystemRoot%\MEMORY.DMP to D:\TEMP\MEMORY.DMP. Restart the computer if changes are made.

Move Personal Folders to Another Drive

The personal folders of the PC’s users are on the same drive as Windows by default. For PCs with multiple drives the personal folders (Documents, Music, Video etc.) can be moved to a hard disk with more room. The process is easily done with Windows Explorer. With Windows Explorer open locate the personal folder for the logged on user (e.g. Documents, Music, Pictures etc.), open the context menu (usually right-click). Select Properties. On the Location tab enter the new location (on a different hard drive with plenty of space) and click OK. Select to confirm creation of the new location and select Yes to confirm moving of the files. Full details on moving personal folders is in the article Move My Documents and Other Personal Folders in Windows 8.1, 8 and 7.

Move the Page File

A powerful PC may have 8GB or 16GB or RAM (memory). Less powerful computers may use a disk file call the Page File to simulate more memory, known as virtual memory. The page file (pagefile.sys) is on the system drive by default. If the computer has another drive (and if it is a faster drive) the page file can be moved to another drive. This can save space on the system drive. To change the page file location use the Advanced systems settings (in Control Panel open System and Security and select System. For the left hand list select Advanced system settings.) On the Advanced tab under Performance select the Settings button. Select the Advanced tab on the Performance Options dialogIn the Virtual Memory section select the Change button.

On the Virtual Memory dialog select a hard drive with free space, ideally the fastest drive in the system. (Uncheck the Automatically manage paging file size for all drives.) With the required drive selected choose the System managed size option (Windows sizes the page file as required). Click OK to close the dialog boxes, a system reboot will be required.

Move Installed Programs

If programs are no longer required they can be removed. For programs that are still used, and the install media is still available (or can be obtain via an Internet download), they can be re-installed. When re-installed instead of selecting the normal install location of C:\Program Files or C:\Program Files (x86) choose a drive with plenty of space and create a programs directory on it. E.g. D:\Programs. When a software installer runs some of them allow the install location to be selected (sometimes directly or via a Customize button). Change the install directory to a sub-directory in the new Programs directory (you may have chosen a different name for the alternative programs directory).

Run a Cleanup Utility Again

After performing the above clean up tips run a third party clean up tool again. It may find other items that can be deleted (e.g. files left over when a program is moved to a new drive).

Defragment the Drive (Does not Apply to Solid State Drives)

A hard drive is made of many thousands of sectors. When files are saved to a hard drive they are saved into the sectors. Sometimes the free sectors are next to each other. Some times they are spread out. This means a file can also be spread out. A sector may not be fully used up by a file as well. This means a drive may have lots of sectors with parts of files and lots of sectors partially filled with parts of files. This is known as fragmentation. A defragmentation utility will rearrange files and parts of files to use the sectors more efficiently. This can free some disk space. This does not apply to Solid State Drives (SSDs) as they use a different technology to store data.

On Windows defragmentation is done automatically at regular intervals. However, sometimes it needs to be run manually. In Windows 8 from the Start screen start typing defrag then select the Defragment and optimise your drives option. In Windows 7 from the Start button select All Programs then Accessories and the System Tools. Select the Disk Defragmenter utility.

Use a Third Party Defragmentation Utility

There are different defragmentation algorithms. Therefore a different defragmentation utility may free up a little more space. Try one if necessary, such as the Piriform Defraggler.

Install a New Disk

If a lot of the above steps could not be completed, because there is only one disk drive in the machine, consider adding a new hard disk. There are lots of tutorials on line showing how to add a hard disk to a computer, alternative someone you know can probably help or knows of someone to help you install a new disk. Adding another hard disk is reasonably easy. Once another disk has been added run through the above list again.

Turn of Windows Hibernation and Delete the Hibernation File

Windows supports a hibernation mode, the system can restart quicker from a power off state if hibernated. To do so the running configuration is stored in a file C:\hiberfil.sys. This can be almost as large as the amount of memory the machine has (e.g. 8 GB). If all the clean up options have been tried and space is still needed turning off hibernation and removing the hiberfil.sys file can free up desperately needed space. This is done via an administrators command prompt with powercfg.exe -h off. See the article hiberfil.sys Windows 8.1 Delete to Free Up SSD Space for full details.

Reformat the Hard Drive and Re-install the Operating System

This is probably the last resort step. Before resetting the PC with a fresh install of the operating system make sure any pictures, files or documents that must be kept have been copied to another location. An on line drive such as SkyDrive, Google Drive or Dropbox helps in this situation. Again if not sure how to do this find someone who can help or research on line.

Running low or running out of disk space can cause a PC to grind to a halt. However, by performing a disc clean up to free up disk space normal service can be resumed. This article has provided a few tips on how to achieve that.