Ive used mdadm and lvm raids in production since about 2004 without data loss and you backup anyway right. How to set up software raid 1 on an existing linux distribution. A software raid can also be affected if the host computer is heavily loaded. Today we dive into what the differences are and whe we choose them. It combines multiple inexpensive, small disk drives into an array of disks in order to provide redundancy, lower latency maximizing the chanc. It is generally fine, however, to use windows software raid on simple storage. My experience with hardware and fake hardware raid is that as long as you stay with the same vendor, the raid metadata will be recognized ive seen this when moving drives between various hp, areca and lsi hardware raid controllers, and with intel, amd and even via hostraid i was pretty surprised when i connected a 250gb hard drive from some old amd desktop box to a hp g1 microserver, and. If you configured the raid via software raid mdadm the use that. Software vs hardware raid nixcraft linux tips, hacks. Can i detect hardware raid infromation from inside linux. With this program, users can create a software raid array in a matter of minutes.
One performance story i can give, is with some hp servers i configured as some fairly kickass splunk servers. Is there a way for me to detect if im using hardware raid from inside of linux, and figure out all the information about it such as type of raid, available drives without turning off the server, physically pulling the drives out, and reading their labels. It covers an overview of hardware raid solutions, the differences between software and hardware raid offerings, and information regarding the configuration of hardware raid on hp linux workstations. The hardware dominates in block output, getting 322mbsec aginst the 174mbsec achieved by software for aligned xfs, making for a 185% speed increase for hardware over software. Comparing hardware raid vs software raid deals with how the storage.
Linux software raid provides systems administrators with the means to implement the reliability and performance of raid without the cost of hardware raid devices. Hardware raid offers better reliability compared to software raid. Solved using opmanager to monitor software raid linux. Windows software raid vs hardware raid ars technica. Microsoft, various linux flavors as well as openbsd, freebsd, netbsd and solaris unix. Hardware raid has the ability to take a group of drives and make it appear as a single drive. How to create a software raid 5 in linux mint ubuntu. Im about to start a new server build for home media storage. Software vs hardware raid performance and cache usage server. The distinction between hardware raid and software raid is in location of the raid mode implementation. However this also fundamentally precludes integration of features into the os and file system. My own tests of the two alternatives yielded some interesting results.
Upgrading is a pain as you need to keep track of ospatches and. Linux software raid provides redundancy across partitions and hard disks, but it tends to be slower and less reliable than raid provided by a hardware based raid disk controller. This site is the linux raid kernel list communitymanaged reference for linux software raid as implemented in recent version 4 kernels and earlier. For software raid i used the linux kernel software raid functionality of a system running 64bit fedora 9. The metadata is stored on the disks only because there is no controller. Do i let the card configure raid 6 or use linux raid. The most popular linux alternative is hardinfo, which is both free and open source. Ive been hoping other people would post with some experience, because im in the middle of a decision and am leaning toward software but just basically fear the unknown. Hardware vs software find out the 8 most important differences. A raid can be deployed using both software and hardware.
Software raid is part of os, so no need to spend extract money. Difference between software raid and hardware raid in high level is presented in this video session. A over heating hardware may damage that particular hardware, other hardware in the surrounding or may crash the whole system. So, just for fun i decided to let the raid controller export each disk individually and use the linux software raid and see what performance that would give. Linux cant see a raid array created in windows and vice versa. For this reason, users regularly create a software raid on linux to satisfy their large data needs. Hardware raid vs software raid, is hardware raid portable. But with budget favoring the software raid, those wanting optimum performance and efficiency of raid will have to go with the hardware raid. In a hardware raid setup, the drives connect to a special raid controller inserted in a fast pciexpress pcie. Fake raid is raid that is at least partially implemented in software in the driver itself, rather than in hardware.
Create 4 raid 1 devices and let software make a raid 5 of that or create raid 1 with 4. I am trying to build a server to play with for media sharingstreaming intel hardware z77, 3770k. What is the difference between hardware raid and software raid. Hp workstations for linux installing and configuring sas. In a hardware raid setup, the drives connect to a raid controller card inserted in a fast pciexpress pcie slot in a motherboard. It should replace many of the unmaintained and outofdate documents out there such as the software raid howto and the linux raid faq. How to set up software raid 0 for windows and linux pc gamer. That duplication also makes hardware raid more expensive than software raid. Mar 26, 2015 the problem with software raid is that it only exists in the os it was created in. Linux mdraid drivers can detect and use software raid arrays that use the intel matrix raid. The advantage of software raid is that your raid sets are not dependent on a certain controller or format and that you receive bugfixes and software updates easily through the software update process.
Linux md raid is exceptionally fast and versatile, but linux io stack is. An example of a hardware raid device would be one that connects to a scsi controller and presents the raid arrays as a single scsi drive. Jun, 2016 comparing hardware raid vs software raid setups deals with how the storage drives in a raid array connect to the motherboard in a server or pc, and the management of those drives. Jul 07, 2009 a redundant array of inexpensive disks raid allows high levels of storage reliability. Hardware raid solutions require specialized hardware. The main surprise in the first set of tests, on raid5 performance, is that block input is substantially better for software raid. Obviously performance of hardware raid vs software raid relies immensely on the controllers used in either case. Favoring hardware raid over software raid comes from a time. Software raid in the real world backdrift backdrift.
On the software side, todays software raid is superfast at least with linux and bsd. Hardware raid will cost more, but it will also be free of software raid s. Nov 03, 2007 so, just for fun i decided to let the raid controller export each disk individually and use the linux software raid and see what performance that would give. May 24, 2005 scott lowe responds to a techrepublic discussion and one members raid dilemma. Current linux kernels support raid both hardware and software for many disk devices and controllers. Linux file systems are generally fragile enough without throwing software raid and questionable hardware into the mix. Ive ordered an areca 1280ml 24 port sata controller. Firstly linux software raid is so well written in the kernel now that very little of the traffic actually hits the cpu. How to monitor a raid array in ubuntu server sookocheff.
Not sure if that helps but i am going by the direction of my peers and upper management here. Monitoring and managing linux software raid prefetch. Hardware is the tangible component that is associated physically with the computer system, whereas software is the intangible component of the computer system. You can install webmin and use the linux raid and permissions. The software raid works on partition level and it can sometime increase complexity if you mix different partitions and hardware raid. And for all the other tests i did software raid outperformed the hardware raid. I do not know how well linux software raid supports hot spares. A software raid can be prone to data corruption, due to the fault of the raid software or driver that is being used. One reason most of us here do not use mdadm tool is that it is mainly used for software raid and we always recommend hardware raid.
Two of the main challenges are shrinking budgets for hardware, software, and staffing and short deadlines in which to deliver solutions. But the real question is whether you should use a hardware raid solution or a software raid solution. Additionally, hardware assisted software raid usually comes with a variety of drivers for the most popular operating systems, and therefore, is more os independent than pure software raid. Want to get an idea of what speed advantage adding an expensive hardware raid card to your new server is likely to give you. Hardware raid versus software raid red hat enterprise linux. To enable software raid on dells th generation of poweredge systems or later. Use onboard sata and mirror the ssd drives through server 2008 r2 builtin raid. Not to mention the performance hit under heavy io not having a dedicated hardware controller handling all the striping and parity operations. This little utility monitors the health of your windows software raid. Hardware raid has made significant advances in recent years including.
Hardware raid if provided by the enclosure as opposed to an adapter in your server can vary by vendor. A brief history of raid raid has been around since 1970s 1989 berkeley paper was a taxonomy 1989 witnessed the first raid 5 in software 1990s saw many hardware raid 3, 5s lsi, 3ware, maxstrat, highpoint, intel 1990s also saw the introduction of raidframe mdraid came along in 2001. It can either be performed in the host servers cpu software raid, or in an external cpu hardware raid. Software vs hardware raid nixcraft nixcraft linux tips. We list the pros and cons of hardware vs software raid to help you decide which. Benefits and drawbacks of hybrid, hardware assisted software raid. Linux server this forum is for the discussion of linux software used in a server related context. Hardware vs software is a comparative topic that are related to components of the computer. It is used to improve disk io performance and reliability of your server or workstation. Bsd opensolaris and linux raid software drivers are open source. Here are some tips on raid levels and some feedback on the software vs. Its based on java, but can easily be called periodically from windows task scheduler, andor at system startup configuration and batch file is included.
There are no advantages to fake raid or expensive real hardware raid controllers that i know of. But is there any kind of software i can use that will monitor both the hds. I see some of the manufacturers say they work with linux, or major linux releases. I would like to add a sas raid controller card, but i am not able to find anything that says it willwont work with ubuntu. The problem well at least usually is that the drivers required arent open sourced and are not usually available for linux based systems. Now my question is that this is all done in hardware. Software or hardware raid i am planning on purchasing a new server soon and would like use two dell ssds in raid 1 configuration using windows server 2008 r2. Feb 28, 2018 raid redundant array of independent disks is one of the popular data storage virtualization technology. Hardware raid configuration is usually done via the system bios when the server boots up, and once configured, it is absolutely transparent to linux. Im not a big fan of software raid on linux nor cheapie white box hardware. If that doesnt suit you, our users have ranked 32 alternatives to open hardware monitor and six of them are available for linux so hopefully you can find a suitable replacement.
Okay, its not unknown for several disks to fail simultaneously, and if your raid array consists of a bunch of drives all bought at the same time, for the array, the odds of that happening are painfully high batches of disks tend to have similar lifetimes. If properly configured, theyll be another 30% faster. Hardware raid and software raid are both important storage tools that we use with our systems. Flexibility is the key advantage of an open source software raid, like linux mdadm, but may. Plug them in and they behave like a big and fast disk. We just need to remember that the smallest of the hdds or partitions dictates the arrays capacity. You can benchmark the performance difference between running a raid using the linux kernel software raid and a hardware raid card. So, if you are running a debianbased server and wish to monitor the state of your raid array you really dont have to do anything at all. The hardware based array manages the raid subsystem independently from the host and presents to the host only a single disk per raid array. In a hardware raid setup, the drives connect to a special raid controller inserted in a fast pciexpress pcie slot in a motherboard. Scott lowe responds to a techrepublic discussion and one members raid dilemma. Numerous server oses support raid configuration, including those from apple, microsoft, various linux flavours as well as openbsd, freebsd. The cost is lower because no additional hardware raid controller is required.
Swapping raid type between windows and linux operating systems by using software raid hii. Because all of the work is done on a separate controller card, there is no impact on the server if you have an older processor or decidedly heavy workload. Software raid is managed only from with the operating system. It assumes a basic understanding of computer hardware, filesystems, and the linux operating system. We can use full disks, or we can use same sized partitions on different sized drives. Hardware raid monitoring in dell servers i have a dell poweredge t320 server equipped with a dell perc h710 controller, this is based on the lsi sas 2208 megaraid chip. Is there software that will monitor hardware raid anandtech. Below is an example of the output if both disks are present and correctly mounted. Apr 28, 2017 how to create a software raid 5 on linux. I still prefer having raid done by some hw component that operates independently of the os. Lets start the hardware vs software raid battle with the hardware side. How to set up a software raid on linux addictivetips. It sounds like you configured the raid via the bios though so definitely use that. Software vs bios vs hardware raid ars technica openforum.
Software raid, as you might already know, is usually builtin on your os and unlike a hardware raid, you will need to spend a little extra on a controller card. Psensor is a very useful tool which lets you see those gray areas of system monitoring which is often overlooked upon i. I want to know what would be the best configuration for this. Heavy processing can cause some pieces of data to be delayed by a small amount of time. Psensor a graphical hardware temperature monitoring tool. May 28, 2010 it turns out that, by default, a daemon job to monitor the array with the mdadm monitor command shown above is run at startup and will send mail to root for any strange occurrence.
Many of the horror stories that come to the linux raid mailing list are down to a simple lack of monitoring. Unlike hardware raid, software raid uses the processing power of the operating system in which the raid disks are installed. Hardware redundant array of inexpensive disks raid and software raid are two main ways for setting up raid system. What is the difference between a software and hardware raid. Whether software raid vs hardware raid is the one for you depends on what you need to do and how much you want to pay. Given that you can safely move the entire enclosure from one server to another with the raid intact but youd have to make sure your new server knew to use it e. It means more people can fix problems as compare to a closed source. You can check the status of a software raid array with the command cat procmdstat. Setting up a storage pool has gotten easier on linux over the years, thanks to tools like mdadm. A redundant array of inexpensive disks raid allows high levels of storage reliability. Installing suse linux enterprise server 12 service pack 1 on perc s controller by using virtual media. Raid redundant array of independent disks is one of the popular data storage virtualization technology.
This integration is really what has allowed software raid to dramatically outpace hardware raid. Difference between hardware raid and software raid. The kernel supports all basic raid modes and complex raid devices can be created by using raid devices as logical partitions. The linux software raid stack is just as much of a component as a hardware card, and its failure. Under windows dell has a utility called openmanage which can report when a drive in an array fails. There is great software raid support in linux these days. I do agree though, that hardware raid is the best choice on business class windows servers or even important. That said, at work i maintain a handful of dell r710 servers using dell h700 and 6i hardware. There are many alternatives to open hardware monitor for linux if you are looking to replace it. Comparing hardware raid vs software raid setups deals with how the storage drives in a raid array connect to the motherboard in a server or pc, and the management of those drives. Areca and lsi hardware raid controllers, and with intel, amd and even via hostraid i was pretty surprised when i connected a 250gb hard drive from some old amd desktop box to a hp g1 microserver, and the controller told me that raid is degraded. For things like simple mirroring raid1 the data just needs to be written twice and the drive controller can do that itself with instructions from the kernel so no need to get cpu involved at all. It also permits users to reconfigure arrays without being restricted by the hardware raid controller.
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