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backup interview questions

Top backup frequently asked interview questions


SQL Server 2008 Express - "Best" backup solution?

What backup solutions would you recommend when using SQL Server 2008 Express? I'm pretty new to SQL Server, but as I'm coming from an MySQL background I thought of setting up replication on another computer and just take Xcopy backups of that server.

But unfortunately replication is not available in the Express Edition.

The site is heavily accessed, so there has to be no delays and downtime. I'm also thinking of doing a backup twice a day or something.

What would you recommend? I have multiple computers I can use, but I don't know if that helps me since I'm using the Express version.


Source: (StackOverflow)

Complete restore of linux system

I am familiar with using rsync to back up various files from my system but what is the best way to completely restore a machine.

What I have tried in the past is:

  1. Do a basic format/reinstall from the Fedora install disks
  2. Make sure networking is enabled
  3. Copy everything from rsync backup over the top of the newly installed system

This way sort of works but I do not think every package that was installed works 100% afterwards.

I want to be able to restore my system with the minimum amount of effort and everything work the same as at the moment the backup was taken. Also if possible install to other machines and essentailly have two machines with the same packages and data.


Source: (StackOverflow)

Do snapshots + RAID count as a good on-site backup solution?

The two main reasons I can think of for taking backups seems to be taken care of when I use both snapshots and RAID together with btrfs. (By RAID here, I mean RAID1 or 10)

  • Accidental deletion of data: Snapshots covers this case
  • Failure of a drive and bit rot
    • Complete failure: RAID covers this case
    • Drive returning bad data: RAID + btrfs' error correcting feature covers this case

So as an on-site backup solution, this seems to work fine, and it doesn't even need a separate data storage device for it!

However, I have heard that both RAID and snapshots aren't considered proper backups, so I'm wondering if I have missed anything.

Aside from btrfs not being a mature technology yet, can you think of anything I've missed? Or is my thinking correct and this is a valid on-site backup solution?


Source: (StackOverflow)

How can I do a dump of only the table structure in PostgreSQL?

In a similar vein to this question, how would I do a schema-only dump in PostgreSQL?


Source: (StackOverflow)

How to backup a full Centos Server?

I switched a few weeks ago from a dedicated server to a VPS. Now that everything is working well on the VPS I would like to shutdown the dedicated server and close my account with the hosting company.

For peace of mind and in order to be more safe I would like to do a full backup of the server before stopping it.

The best would be a backup that I could browse if I find that I need a something in the backup.

What would be the best solution from command line?

Update :

Medium : Network


Source: (StackOverflow)

Automatic postgres backup

What is the best way to automatically backup a Postgres database on Linux every day?


Source: (StackOverflow)

Best practices for backup checking?

It is a common situation, when administrator makes system for automatic backuping and forgets it. Only after a system fails administrator notices, that backup system has broken before or backups are unrestorable because of some fault and he has no current backup to restore from... So what are best practices to avoid such situations??


Source: (StackOverflow)

Backup strategy for developer-focused Apple environments?

It's interesting to see the technological split between structured corporate environments and more developer-driven/startup environments. Some of the Microsoft technologies I take for granted (VSS, Folder Redirection, etc.) simply are not available when managing the increasing number of Apple laptops I see in DevOps shops.

I'm interested in centralized and automated backup strategies for a group of 30-40 Apple laptops...

How is this typically done safely and securely, assuming these are company-owned machines (versus BYOD)?

  • While Apple has Time Machine, it's geared toward individual computer backups and doesn't seem to work reliably in a group setting. Another issue with these workstations is the presence of Vagrant/Virtual Box VMs on the developers' systems. Time Machine and virtual machines typically don't work well unless the VMs are excluded from the backup set.
  • I'd like a push-based backup process with some flexible scheduling options.
  • I know how to handle the backend storage, but I'm not sure on what needs to be presented to the client systems.
  • Due to the nature of the data here, cloud-based backup may not be a viable option.

Any suggestions about how you handle this in your environment would be appreciated.

Edit: The virtual machine backups are no longer important. They can be excluded from the process and planning.


Source: (StackOverflow)

Does Rsync Allow Files To Be Synced Both Ways?

I have backed up a linux web server using rsync with cygwin. I now have a perfect copy of the server on my windows laptop. If i delete or modify a file on my laptop and run rsync again with cygwin will it delete/update the same file on the server? Im under the impression that if i delete/modify on the server and run rsync on my laptop it will delete/modify the local file on my laptop but does this work in reverse?


Source: (StackOverflow)

Are encrypted backups a good idea?

I'm in charge of a small set of laptops and wanted to get some sort of automated remote (over WAN) backups going; the backups would be going to a RAID drive. Because we don't really have a secure vault to hold all our drives (if someone wanted, they could smash the windows and take our drives), I was considering on using encryption, maybe something like duplicity (http://duplicity.nongnu.org/). I've discussed this with a few of the developers, but they seem convinced that encryption is a bad idea because a single bad bit could ruin the whole block. However, I haven't actually heard of any horror stories where this happened. What's your opinion? Do the benefits outweight the risks with encryption?


Source: (StackOverflow)

Cliffhanger: The backups are right... here... right?

At my work, backups have a surprisingly low priority. The backup strategy was implemented a while ago, and since then it's just assumed the backups are fine. If you ask the sysadmins, they'll say everything is backed up.

But then, when you ask for a SPECIFIC backup, half the time they are not there:

  • The disk got full
  • The tape failed
  • Looks like someone disabled the backup job
  • The network connection had downtime
  • We ordered that disk years ago, but finance hasn't approved the purchase order
  • The files are corrupt
  • File contains wrong database
  • Only transaction log backups (useless without a full one)

A few weeks ago, disaster came real close as one of the servers lost one too many raid disks. Luckily one disk was still kind enough to copy the data, if you tried a lot of times.

But even after that near-disaster, I can't seem to convince the sysadmins to improve the situation. So I'm wondering, any tips for opening people's eyes? It seems to me we're walking along the edge of a cliff.


Source: (StackOverflow)

Do I still need a backup if I have a redudant storage system with rollback capabilities?

My organization recently bought a storage system. It has 1.5Petabyte, with RAID6, and there is an online synced mirror in a physical different location.

The system allows rollback / file recovery, by default allowing up to 30 days but this can be increased.

There is a discussion going on if we need some kind of extra backup for data living only on the storage.

The system has a very good level of redundancy, it has geographical redundancy and allows up to some extent rollback which means we can recover up to the defined time (30 days by default) old data or accidentally deleted data.

Given this scenario does it still make sense to have a "traditional" backup? By traditional, I mean a dedicated backup system, with snapshots that we can retrieve in case something goes wrong.

Do we really need it? Am I missing something? Am I just thinking by the traditional way and being over zealous?


Source: (StackOverflow)

protocol version mismatch -- is your shell clean?

When following the instructions to do rsync backups given here: http://troy.jdmz.net/rsync/index.html

I get the error "protocol version mismatch -- is your shell clean?"

I read somewhere that I needed to silence the prompt (PS1="") and motd (.hushlogin) displays to deal with this. I have done this, the prompt and login banner (MOTD) not longer appear, but the error still appears when I run:

rsync -avvvz -e "ssh -i /home/thisuser/cron/thishost-rsync-key" remoteuser@remotehost:/remote/dir /this/dir/

Both ssh client and sshd server are using version 2 of the protocol.

What could be the problem? Thanks.

[EDIT] I have found http://www.eng.cam.ac.uk/help/jpmg/ssh/authorized_keys_howto.html which directs that it is sometimes necessary to "Force v2 by using the -2 flag to ssh or slogin

 ssh -2 -i ~/.ssh/my_private_key remotemachine"

It is not clear this solved the problem as I think I put this change in AFTER the error changed but the fact is the error has evolved to something else. I'll update this when I learn more. And I will certainly try the suggestion to run this in an emacs shell - thank you.


Source: (StackOverflow)

Confidential Documentation and the role of the Sysadmin

I've got another interesting one.

I'm about to backup and reinstall the HR Administrator's PC. I suspect that the fastest way to do this is to use the Windows 7 Transfer tool, and create a backup of the entire Users and Settings profiles on the NAS.

I don't see a problem with this.
She claims that nobody else should be able to see the information on her computer. Fair enough. I think that the systems administrator (me), should be in a significant enough level of trust to be able to make a backup, no questions asked, and delete the backup once the task is complete.

Her view is, that nobody (not even the other directors) should be able to view the HR documentation on her PC.

We already have a semi-backup (files, not user-state) on box.net, which does allow granular access to various users.

Questions:

1) Which one of us is nuts, her or me?

2) Do you trust your sysadmins to take backups of company policy / HR files?

3) Does anyone have a LART?


Source: (StackOverflow)

GIT as a backup tool

On a server, install git

cd /
git init
git add .
git commit -a -m "Yes, this is server"

Then get /.git/ to point to a network drive (SAN, NFS, Samba whatever) or different disk. Use a cron job every hour/day etc. to update the changes. The .git directory would contain a versioned copy of all the server files (excluding the useless/complicated ones like /proc, /dev etc.)

For a non-important development server where I don't want the hassle/cost of setting it up on a proper backup system, and where backups would only be for convenience (I.E. we don't need to backup this server but it would save some time if things went wrong), could this be a valid backup solution or will it just fall over in a big pile of poop?


Source: (StackOverflow)