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#Softraid vs hardware raid install
#Softraid vs hardware raid software

So in the event of a disk controller failure you could simply replace the controller (or the whole server) and the disks will remain usable. Additionally you are no longer bound to a specific piece of hardware. You’ll get the same core features as hardware with a standard management and monitoring suite.

#Softraid vs hardware raid software

It seems to me that if you care about the integrity of your data and do not need ultra-intense IO performance then software RAID is a good choice. And what about manageability after initial deployment? But at the end of the day if you loose your data then it’s gone. I can certainly understand the argument of simple deployment and having a vendor to blame. I’ve seen systems panic when a failed disk was physically removed before being logically removed. Disk replacement sometimes requires prep work-You typically should tell the software RAID system to stop using a disk before you yank it out of the system.I have yet to see a real-world performance degradation introduced by this, however. Additional load on CPU – RAID operations have to be calculated somewhere and in software this will run on your CPU instead of dedicated hardware.Slower performance than dedicated hardware – A high end dedicated RAID card will match or outperform software.– Servers won’t come mirrored out of the box, you’ll need to make sure this happens yourself.

#Softraid vs hardware raid install

Typically need to incorporate the RAID build into the OS install process.– These tools are often well documented but not as quick to get off the ground as their hardware counterparts. Need to learn the software RAID tool set for each OS.Very flexible – Software raid allows you to reconfigure your arrays in ways that I have not found possible with hardware controllers.Unless you are performing tremendous amounts of IO the extra cost just doesn’t seem worthwhile.

Good performance – CPUs just keep getting faster and faster.

Standardized monitoring (for each OS) – Since the toolkit is consistent you can expect to monitor the health of each of your servers using the same methods.

Standardized RAID configuration (for each OS) – The management toolkit is OS specific rather than specific to each individual type of RAID card.

Hardware independent – RAID is implemented on the OS which keeps things consistent regardless of the hardware manufacturer.

Inflexible – Your ability to reshape, split and perform other maintenance on arrays varies tremendously with each card.

Lack of standardization between controllers (configuration, management, etc)– The keystrokes and software that you use to manage and monitor one card likely won’t work on another.

Additional cost – Hardware RAID cards cost more than standard disk controllers.

Often you are tied to specific piece of software that the vendor provides.

Monitoring implementations are all over the road – Depending on the vendor and model the ability and interface to monitor the health and performance of your array varies greatly.

This is especially bad if working with a discontinued model that has failed after years of operation

On-Disk meta data can make it near impossible to recover data without a compatible RAID card – If your controller goes casters-up you’ll have to find a compatible model to replace it with, your disks won’t be useful without the controller.

Proprietary – Minimal or complete lack of detailed hardware and software specifications.

Performance improvements (sometimes) – If you are running tremendously intense workloads or utilizing an underpowered CPU hardware raid can offer a performance improvement.

Easy to replace disks – If a disk fails just pull it out and replace it with a new one.

Easy to set up – Most controllers have a menu driven wizard to guide you through building your array or even are automatically set up right out of the box.

After cursing loudly at the RAID controller I started wondering if the pros of hardware raid really outweigh the cons for a general purpose, nothing special, 1 or 2U server that just needs disk mirroring.

Luckily I had a similar system sitting idle, so I tested the same disks in this server and they worked just fine. Upon reboot the hardware controller says to me “sorry buddy, I don’t see any drives” and wouldn’t boot. But when replacing the failed disk with a shiny new one suddenly both drives went red and the system crashed. Today a server with a hardware RAID controller reported (when I say reported I actually mean lit a small red LED on the front of the machine) a bad disk, which is not uncommon. I’m a sysadmin by trade and as such I deal with RAID enabled servers on a daily basis.