Planning for Data Recovery
Let's say we perform full backups once every week, and differential backups daily. In the worst case scenario we'll lose close to
24 hours of data changes, that's not bad.
What are some concerns using a file server or commercial NAS device
But what do you do once your back up data grows to fill that one disk? Are they even making disks larger than 10 terabytes yet? Another thing to worry about is what do you do if that one disk holding all your backed up data fails.
Some examples of cloud services designed for syncing and backing up files across platforms and devices are...
Dropbox, Apple iCloud and Google Drive, which are simple and straightforward to use.
One more thing backup systems can do to help save space is
File compression
When setting up self managed backups what are some of the questions you should ask?
How do you grow the disk capacity when you need more storage space? How do you handle the failed hard disk? Because hard disks will fail eventually, by the way, it's important to call out these options aren't mutually exclusive.
What is a disadvantage of onsite backup solutions?
If there is an unexpected event, like a fire, systems we were backing up along with the backup server had been lost in the fire. Then you have lost everything.
What is the drawback of full backups on a regular basis
In the case of data that doesn't change very often, like operating system configuration files, this approach can be inefficient. You're backing up multiple copies of data that isn't changing, which waste space and uses bandwidth unnecessarily.
Disaster recovery testing should have what happen when testing
It should have different teams including I.T. support specialists going through simulations of disaster events. They'll test and evaluate how well-prepared or unprepared your organization is when lots of unexpected events.
command line utility rsync.
It's a file transfer utility that's designed to efficiently transfer and synchronize files between locations or computers. isn't explicitly a backup tool, but it's very commonly used as one.
Advantage of off site backup
Offsite backups better prepare us for catastrophic events that can wipe out data from an entire office
Rsync supports compression and you can use ____________ to securely transfer data over a network.
SSH
Disadvantage of off site backup
Sending data offsite means that you need to transmit the data outside of your network.
Why is ensuring reliable backups for client devices is a bit more challenging than infrastructure devices.
There likely to be lots of more client devices to backup compared to infrastructure ones. Plus there are laptops, phones and tablets that won't be in the office all the time.
data tapes
These are a lot like audio cassette tapes since they use spools of magnetic tape run through machines that allow data to be written to and read back from the tape.
How long do you need to hang on to backups for?
This answer will impact your long term storage needs and overall costs to maintain a backup system.
Where will the Offsite backup be?
This could be another backup server that you control in a different office, or a cloud hosted backup service.
Apple has a first party backup solution available for their, Mac operating systems called
Time Machine.
File compression
When creating a backup all the files and folder structures will be copied and put into an archive.
difference between regular incremental backups and differential backups.
While a differential backup backs files that have been changed or created, and incremental backup is when only the data that's changed in files is backed up.
there's a pretty cheap and easy to maintain option out there for storing backup data on site. These are...
You can use a commercial NAS device, or configure a filer server with a large amount of disk space.
Time Machine has two modes of operation
a file based version where files are backed up to a zip archive. the system image where the entire disk saved block by block to a file.
When doings a distaster recovery test you should run a variety of scenarios. These scenarios can be anything from
a simulated natural disaster, like an earthquake to a fictional, event like a horde of zombies shutting down an office.
In a perfect world, you should only be backing up data that's
absolutely necessary for operations and can be found in another source.
storing data on a RAID array doesn't protect against
accidentally deleting files, or malware corrupting your data.
These simulated events are the perfect way to discover
any gaps in your planning.
One approach, which balances cost with convenience, is to
archive older data using a slower but cheaper storage mechanism.
Tape storage is pretty cheap, but isn't
as easy or quick to access as data stored on hard drives or solid state drives.
RAID isn't a back up solution, it's a
back up solution, it's a data storage solution that has some hardware failure redundancy available in some of the RAID levels.
Why would a recovery of data using incremental backups be more time consuming
because the most recent version of backed up data has to be recreated by integrating the last full backup with each incremental backup that follows. For super large files that are changing frequently this could require a lot of time to process.
What is a possible drawback with incremental backups
because this approach only sorts differences in the files that have changed since the last incremental backup, it's possible that all incremental backups are needed to fully reconstruct the files. If one of these incremental backups is missing or corrupt it might not be possible to recover data any more recently than the last full back up. Another drawback is that recovery might be more time consuming.
On site, or self managed backups, could be as simple as
buying a commercial NAS device, loading it with a bunch of hard drives, and sending data to it over the network. This would definitely work, but it might not be the best long term solution.
One solution to user backups is to use
cloud service designed for syncing and backing up files across platforms and devices.
differential backup
copies all changes made since the last full backup
Disaster Recovery testing
critical to ensuring a well functioning recovery system. document the procedure and make sure you regularly test the documentation to make sure it works now and in the future.
What types of things should disaster plans include?
customer data, system databases, system configs and financial data.
The standard medium for archival backup data storage is
data tapes
What are some reasons data recovery might be needed?
device that contains data was physically damaged, or an attacker performed malicious actions, or malware deleted critical data.
In Time Machine, System image backups support
differential mode, only backing up blocks on the disk that have changed since the last backup.
Backing up data isn't free. Every additional file you back up takes up little more
disc space, increasing the overall costs of your backup solution.
regular incremental backups are more efficient in terms of
disk space, and time required compared to differential backups.
Restoration procedures should be
documented and accessible so that anyone with the right access can restore operations when needed.
It is good practice to perform infrequent full backups, while also
doing more frequent differential backups.
What types of data should be backed up?
e-mails, sales databases, financial spreadsheets, server configurations, and databases, should all be included.
One of the most important techniques you'll learn is how to
effectively backup your data.
In Time Machine, File based backup support
either complete backups or incremental ones.
The resulting backup data that's stored should also be
encrypted at rest.
There's a couple of ways to perform regular backups on data that's constantly changing.
full backup differential backup regular incremental backups. file compression
you'll want to use frequent incremental backups along with less frequent
full backups
If you use differential backup you should not stop using
full backups. Over time you wind up tracking and storing lots of copies of files that change a lot, which will also take up more and more disk space over time. To avoid this it's a good practice to perform infrequent full backups, while also doing more frequent differential backups.
Your organization may continue to grow and your backup needs should
grow with it
When choosing a back up plan make sure that you account for future
growth and choose a solution as flexible enough to easily accommodate increases in data backups.
The best way to be prepared for a data-loss event is to
have a well-thought out disaster plan and procedure in place.
How often you perform a full backup will depend on
how far back you want changes to be tracked.
Once you've figured out what data you like to back up, you should find out
how much total data you currently have.
post-mortem
is a way for you to document any problems you discovered along the way, and most importantly, the ways you fixed them so you can make sure they don't happen again. After data loss and recovery
Data Recovery
is the process of trying to restore data after an unexpected event that results in data loss or corruption.
regular incremental backups.
is when only the data that's changed in files is backed up.
Archives are useful for
keeping files organized and preserving full structure.
Data tape storage system is usually used for long term archival purposes, where data isn't
likely to be needed. If it is needed some delay in getting the data isn't a concern.
Data can be backed up either
locally to systems on site, or the backup data can be sent upside to remote systems.
full backup on a regular basis, which involves
making a copy of the data to be fully backed up. The full unmodified contents of all files to be backed up is included in this backup mechanism whether the data was modified or not.
Offsite backup involves doing what?
making backups of critical data and sending the backup data offsite to remote systems in a different physical location.
Disaster plans should involve
making regular backups of any and all critical data that's necessary for your ongoing business processes.
RAID arrays are a great, inexpensive way of creating a lot of data capacity, while
minimizing risk of data loss in the event of disk failure. They can even be flexible enough to allow future growth in disk capacity.
There's nothing stopping you from implementing both
on site and offsite backups. it's often recommended to have both if it's within your organization's budget.
Disaster recovery testing should be a regular exercise that happens
once a year or so.
Depending on the characteristics desired from the RAID, various RAID levels prioritize features like
performance, capacity, or reliability.
If one of these incremental backups is missing or corrupt it might not be possible to
recover data any more recently than the last full backup
Using SSH, it can also synchronize files between
remote machines making it super useful for simple automated backups.
If you backed up your data on the damaged device you could...
restore the data that was lost.
RAID array
stands for Redundant Array of Independent Disks, it's a method of taking multiple physical disks and combining them into one large virtual disk.
Besides archiving the files, backups can also be compressed, this is a mechanism of
storing the same data while requiring less disk space by using complex algorithms. This means that space savings from compression will depend on what you're backing up.
Time Machine
supports restoring an entire system from backup or individual files. It operates the using an incremental backup model. It even allows restoring older versions of backup files.
Cloud services make it easy for users to configure what files or folders they want to have backed up and then ensure the files are
synchronized with what's stored in the cloud.
The other half is a recovery process and that process needs to be
tested regularly
If a device has been damaged, you might be able to recover data from
the damaged hardware.
Since Offsite backups will often contain sensitive and confidential business data, it's important
the data is handled securely and stored in a way that prevents unauthorized access. preferably encrypted via TNS.
The advantage of onsite backup solutions is that
the data is physically very close. This makes accessing the data a lot quicker. You won't need as much outbound bandwidth since you aren't sending the data out of your internal network. If you need to restore data from backups, that should happen pretty quickly since the data is close at hand.
The drawback of file compression is
the expense of restoration To recover data from a backup it needs to be decompressed first. Depending on the size of your backups this could take a lot of time, and disk space to expand.
While a differential backup backs up files that have been changed or created since
the last full backup
an incremental backup is when only the data that's changed in files since
the last incremental backup is backed up
How you go about trying to restore this lost data depends on a few factors.
the nature of the data lost and the presence of backups.
When designing a data backup and recovery plan, what is the first thing you will need to consider?
to figure out is what data you need to backup.
When an unexpected event occurs, your main objective is
to resume normal operations as soon as possible, while minimizing the disruption to your business functions.
If you just use differential backups over time you wind up
tracking and storing lots of copies of files that changed a lot. which will also take up more and more disk space over time.
To recover data from a damaged device you may need to
use data recovery software, which can analyze failed hard disks or flash drives and try to locate and extract data files.
teams test their emergency procedures and figure out
what works and most importantly what doesn't.
the advantage of a differential backup
you aren't storing backups of duplicated, unchanging data, only the files that changed are backed up.
What are some trade offs to the safety of offsite backups?
you need to consider things like encryption and bandwidth. Your internet connection will be used to transmit the backup data. Depending on how much data you're sending off site and how fast the internet connection is, this could take a lot of time.
While it's important to have a backup solution for infrastructure and critical systems, you also to think about
your users and their valuable files.
