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16

Why not convert the running systems to Virtual Machines? Most hypervisors like VMware or Hyper-V have a tool to convert a running system to a virtual machine easily. You can then work with a non-production system as you wish before doing anything on a production server. Thanks to @WernerCD Vmware Hyper-V


14

The outcome you want to achieve, and the manner in which you have decided to do it, are very different things. To be blunt, what you want to implement is a bad idea, and if you can somehow manage to make it work, it won't work for very long (or very well). What makes this question difficult to answer is that you've leapt straight to the implementation, and ...


10

Can it be done? Definitely yes. I have copied an entire Linux server by simply packing up the files with tar and extracted them again on the target server. The only caveat I recall was having to remember to use --numeric-owner when extracting. I can't speak for other OS and other tools, but I imagine it is doable with all major operating systems. Should it ...


7

RoboCopy is a command line tool provided by Microsoft that can do mirroring. The Wiki page also mentions a GUI.


7

Copying all of the files could work. It's going to depend on the OS and what kind of copy method. One general problem is trying to copy the system while it is running. Typically at least some of the files will be locked, and therefore won't copy correctly. Using some kind of imaging software while the system is shut down is usually safest (you mentioned ...


6

Well, the REAL answer is that it depends on the RAID controller. There's Hardware RAID and there's 'Fake RAID' -- which is basically a ROM implementation of software RAID. Fake Raid will always require the same controller, just as using a linux software raid will require the same operating system (and sometimes the same kernel module version). Real ...


6

As Clint mentioned in his comment, Robocopy might do the job for you if you need near real time file synching. Here's a snippet of some of the options available: /mon: Monitors the source, and runs again when more than N changes are detected. /mot: Monitors source, and runs again in M minutes if changes are detected. For the full list of options and ...


6

Feasibility Sure, it's possible, because it's not hard to "install" Linux using unconventional means. You could, for example, replicate the server using rsync over SSH. Boot the target machine into a "rescue" image, whether using a Red Hat DVD, Ubuntu live boot, Knoppix, whatever. Partition and format the target machine, and mount the filesystems under a ...


5

Although network bandwidth comes into play in a big way, the absolute number one factor to consider is what is the transaction log generation rate on the principal? If the app and your maintenance doesn't generate any transaction log, then network bandwidth is really irrelevant. If it does generate log, then network bandwidth has to be able to handle the ...


5

Microsoft published a really good whitepaper on database mirroring that includes some good examples on how much performance impact you get from synchronous mirroring. You're totally right in that there's going to be a performance hit. Do a ping from the primary box to the database mirror and look at the round trip times in milliseconds: that's going to be ...


5

I don't think scp alone can do what you ask. You should investigate rsync instead. I use it for backups with a filter to exclude files with names that don't work on NTFS volumes # the exclude is to filter out files with invalid names on NTFS /usr/bin/rsync -rgqoxD --delete --exclude='*[:\?]*' /home/andrewr/src /filer001/syncd/src you can also pass it the ...


5

This would be comonly known as RAID 1+0 or RAID 10. Check whether your controller supports it ;) Being a SAS controller... it should.


5

i'd vote Rsync if the important stuff is within a folder, I.E. rsync -zuvr /home/users/me/myimportantstuff/ /media/usb/whatever/ For disk or partition cloning, use DD. http://serverfault.com/questions/4906/using-dd-for-disk-cloning


5

You can use the "s3cmd" utility with the "sync" option, although I stumbled on your question because I'm trying to figure out if this syncing mechanism is screwing up my duplicity backups.


5

The first question I would ask is do you want this replicated to two servers or more then two servers? For two servers I would go with DRDB, for three or more I would go with gluster. If I/O latency is not a critical concern I would go with gluster. It is pretty easy to setup and could clearly do what you needed. All you need to do is make a gluster server ...


5

I have not yet tried the new LVM segment types, but the overview is that they are support for the Linux MD RAID personalities in LVM. That is, they are RAID levels 1, 5, 6 etc. using the MD code with the eventual goal of removing the duplicate functionality of LVM's mirroring and having both MD and LVM use the same code. This is very new stuff so may not be ...


4

Yep that is exactly what hot swapping is all about. You can pull the disk at any time without having to turn off the server.


4

I don't think this is the complete answer, but some are: /sys /proc /tmp /var/run /var/lock /dev /mnt # The following are stolen from Womble: /var/cache /var/tmp /var/spool


4

I've never used LVM mirroring, but the info you've dug up seems reasonable from what I know of LVM. I'd stick with MD RAID-1, myself.


4

Wget does no more and no less than an actual web browser with the only exception that it can be told to suck a whole site down which it can do without delay and which on a real web-browser is just about impossible to do quickly. I often use it, for example, to grab data in a particular directory hosted at a site as for some jobs it's much more efficient than ...


4

Did you issue the command using sudo so you have elevated privileges? Rsync might also work better for something like that. I'd caution against considering it a backup, as it's just a copy. Backups protect against corruption issues or deleted files. Making copies is more like protecting availability of resources.


4

There's a few disadvantages. Not many. Probably not enough to outweigh the advantages of having a software RAID. Everyday performance is going to suffer...minimally...probably not noticeably at all Rebuilding the RAID is going to kill performance...probably a lot Software RAIDs typically don't give you hot swap ability, meaning a failed drive requires ...


4

I was having the same problem so I whipped up a little program specifically designed to mirror one S3 bucket to another; I call it s3s3mirror. I did try the "s3cmd sync" approach first, but I had a bucket with hundreds of thousands of objects in it, and "s3cmd sync" just sat there, not doing anything but consuming more and more memory until my system died. ...


4

You'd be looking at some form of replication - either merge or transactional. There are plenty of guides to choosing which type would best fit your environment. Of course, what the business tends to demand tends to be impossible if taken literally - e.g. they always want 100% consistent at all times, no latency, no penalties for any types of queries. You ...


4

assuming sda is the original disk, and sdb is the new disk: partition the new drive. if using fdisk, be sure to hit c so it is aligned, and change the partition type to da. sudo mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdb1 missing to create the raid device from the newly partitioned drive. sudo mdadm -Es and copy the output of this to ...


4

The solution I'd use for taking a point-in-time snapshot of a running system is the (free) Idera/R1Soft Hot Copy product. Using this, you can take a clean snapshot and rsync the entire copy (or portions of the copy) to another system.


4

RAID 1 is a mirror. The fact that when you drill down into the virtual disk, you only see Physical Disk 0:0 means that Disk 0:1 has failed and is showing as removed. You could try removing the faulty disk (should be showing with an orange light) and re-inserting it - this sometimes kicks off a rebuild but even if that works you should probably consider ...


4

A couple different things jump to mind first and foremost: First, you already have a static mirror of your site that is designed for just this use-case: Cloudflare. As well as providing your DNS, I assume you have them set up as a CDN to dull the brunt of traffic that is coming towards you. Cloudflare has a feature called Always Online which is intended ...


3

Write cache disabling is always required if you want to minimise the chances of data loss when you have a power cut. It doesn't matter if you have md RAID, LVM, or nothing at all. Your drive can have 16 - 64 MB in the cache on a modern device, and it will dissapear. Unless you value speed over correctness, I'd switch write caching off on drives. ...



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