This site is the linux raid kernel list communitymanaged reference for linux software raid as implemented in recent version 4 kernels and earlier. Raid 5, 2tb, gpt, grub, booting, mounting root centos. How to set up software raid1 on a running system incl. Hi, have struggled with this for a day, too and found a soultion. See the deployment guide section redundant array of independent disks raid or centos 5 faq entry how do i install a software raid on centos 5. Now that both drive are ready, it is time to select configure software raid. At this point the raid module built into the kernel will try to assemble your raid1 array using a nonexistant drive and your secondary, or mirror, drive. It is an advanced tool for raid management that will be used to create a etcnf within the installation environment. Aug 11, 2016 when i perform a software raid 1 or raid 5 installation on a lan server with several hard disks, i wonder if grub already gets installed on each individual mbr, or if i have to do that manually. Solved cant install grub2 on software raid installation. My understanding is that grub1 doesnt know anything about raid and so cant boot off any kind of raid array. Nov 28, 2019 following this, there are also no guides on installing the grub bootloader to both gpt partitioned devices afterwards. Now lets create our raid arrays devmd0, devmd1, and devmd2. Now we have to set up the boot loader to boot to the raid drive.
Contains comprehensive benchmarking of linux ubuntu 7. Update fstab and grub configuration to boot from newly created storage volume. I recently setup a raid 5 setup with 8 4tb drives with mdadm. How to change boot drive on server with raid 5 software raid. You will be asked to partition disks at this point. In the following it is assumed that you have a software raid where a.
This gives the appearance of a hardware raid, because the raid configuration is done using a bios setup screen, and the operating system can be booted from the raid. Grub dont support booting on a raid10 software raid. When the bootloaderstep is entered i selected grub2 each time i. It provides the ability for one drive to fail without any data loss. Gentoo linux x86 with software raid and lvm2 quick install guide. The software raid in linux is well tested, but even with well tested software, raid can fail. Nov 15, 2011 raid5 requires a minimum of 3 drives, and all should be the same size. Raid 6 requires 4 or more physical drives, and provides the benefits of raid 5 but with security against two drive failures. Software raid raid that is is implemented at the software layer without a dedthe need foricated. R410 w software raid always boots to grub shell after linux install appreciate the reply, but i just bit the bullet and installed ubuntu on a flash drive and use fstab to mount partitions of the assembled raid on different parts of the filesystem. This worked well for bios booting since bios just transfers control blindly to the mbr of whatever disk it sees modulo finding a bootable partition flag, etc, etc. How do i install grub on a raid system installation. An alternative approach that might give somewhat better performance and twice the swap area for equivalent partition sizes, at the expense of. Install ubuntu with software raid mdadm for the installation, im using the live server installer for ubuntu server 18.
How do you ensure grub is properly installed on a software raid array in ubuntu. I spent some time yesterday building out a uefi server that didnt have onboard hardware raid for its system drives. It looks like currently most os installers insist on putting boot on a nonraid partition or the kind of raid1 partition that looks like a nonraid partition, even the installers that support raid5 and grub2 im guessing this limitation is a historical relic leftover from grub1. You can check to see that a boot loader is present with.
After creating the physical partitions, you are ready to setup the boot, swap, and arrays with mdadm. Minimum 3 hard drives are required to create raid 5, but you can add more disks, only if youve a dedicated hardware raid controller with multi ports. Find answers to software raid 5 ubuntu grub error 2 from the expert community at experts exchange. Server has 6 2tb drives with 2 software raids on them md0 raid 1 for system and swap and md1 raid 5 for data. Following this, there are also no guides on installing the grub bootloader to both gpt partitioned devices afterwards.
Ubuntu raid 1 step 7 repeat steps for second drive. Raid 5, 2tb, gpt, grub, booting, mounting root post by pjwelsh fri nov 02, 2007 2. Having seen our plain and simple install of ubuntu 12. Grub configuration debian etch page 2 dont let creepy ads follow you around. When typical stuff like grubinstall from a rescue console doesnt work. We can use full disks, or we can use same sized partitions on different sized drives. We will also see the step wise command how to stop and remove raid device by removing raid10 device here. For this you will need to know what your kernel version is. Apr 19, 2018 uefi should be able to boot whatever disk hasnt failed, and grubinstall will write to the raid mounted at bootefi. Proceed through the installer until you get to filesystem. When asked to install bootloader, install to first device. Raid 5, 2tb, gpt, grub, booting, mounting root post by pjwelsh. R410 w software raid always boots to grub shell after linux.
My experience installing centos 5 and centos 6 is that during the installation phase i configured the raid 1 at that time the installation does give you the choice to do this. This article describes how to setup a linux system that can boot directly from a software raid1 device using grub. Hey, i have worked with linux for some time, but have not gotten into the specifics of hard drive tuning or software raid. How to create a software raid 5 in linux mint ubuntu. When i do use software raid, i have made a habit of manually installing grub on the other disks using grubinstall. The red hat customer portal delivers the knowledge, expertise, and guidance available through your red hat subscription. After first boot, consider executing dpkgreconfigure grubpc or dpkgreconfigure grubefiamd64 on efi systems, and install to all devices. I recently setup a raid5 setup with 8 4tb drives with mdadm. Not a software or fake raid, but a full hardware raid that looks like a normal non raid disk. In the following it is assumed that you have a software raid where a disk more than the redundancy has failed. Redundancy can absolutely be expected in a software raid. Creating raid 5 striping with distributed parity in.
Up until windows 8, software raid in windows was a mess. Software raid 5 in ubuntudebian with mdadm zack reed. This article refers to the use of the old grub now known also as grublegacy. Heres a quick way to calculate how much space youll have when youre complete. On the other hand, with raid 5, i dont need a separate boot partition and all drives are equal when it comes to booting. Mar 20, 2011 quote you can simulate a diskpartition failure in software raid by using mdadm.
A combination of drives makes a group of disks to form a raid array or a set of raid which can be a minimum of 2 disks connected to a raid controller and making a logical volume or more, it can be a combination of more drives in a group. Ive tried installing grub on different drives as well as both drives in the array at once, but havent had any luck. Apr 28, 2017 how to create a software raid 5 on linux. It should default to installing grub to devsda, click next. This article describes how to setup a linux system that can boot directly from a software raid 1 device using grub. If you have 2 x 500 gb hdd then total space become 1 tb. When i first tried booting it, the grub screen came up, but selecting any kernel resulted in an endless stream of system messages, and i never got to login prompt. Oct 26, 2017 this gives the appearance of a hardware raid, because the raid configuration is done using a bios setup screen, and the operating system can be booted from the raid.
However, i cant figure out to do a grub setup on a raid 5 array. Use ipvanish to regain control of your data and break free from online tracking. The problem is at the end of the installation, it tries to install grub. Unable to install grub to software raid array in ubuntu. My experience installing centos 5 and centos 6 is that during the installation phase i configured the raid1 at that time the installation does give you the choice to do this. Sep 12, 2015 raid is a method of using multiple hard drives to act as one. Usable space number of drives 1 size of smallest drive. Even if one of the disks in the raid array fails, the system can still boot. It looks like currently most os installers insist on putting boot on a non raid partition or the kind of raid1 partition that looks like a non raid partition, even the installers that support raid5 and grub2 im guessing this limitation is a historical relic leftover from grub1. Solved cant install grub2 on software raid my several installs of raid0 utilized grub 2 with no problems. With the advent of terabyte disk drives, fakeraid is becoming a popular option for entrylevel small business servers to simply mirror 2 1. Where possible, information should be tagged with the minimum. By default it tries my first disk, which gives a fatal error.
Mar 17, 20 having seen our plain and simple install of ubuntu 12. The g has new directives but when i boot and press e on grub menu i get the old command included quiet and rhgb. Software raid red hat enterprise linux 6 red hat customer portal. The above commands helped me fix this issue on centos 6.
I have a dell poweredge t105 at home and i am purchasing the following. Grub seems to want to deal with physical disks that have a readable boot on them. Jun 02, 2016 hi, have struggled with this for a day, too and found a soultion. Its all been running great but the power went out for a minute and when the box came around the raid is gone. Simply ensure that grub is installed on all discs in the array, the bios will try each disc as a separate boot device and that the boot device in the grub config is the raid device name.
Raid5 requires a minimum of 3 drives, and all should be the same size. Raid 5 uses striping, like raid 0, but also stores parity blocks distributed across each member disk. Jun 24, 2005 at this point the raid module built into the kernel will try to assemble your raid 1 array using a nonexistant drive and your secondary, or mirror, drive. When the bootloaderstep is entered i selected grub2 each time i loaded a new raid install. This article addresses an approach for setting up of software mdraid raid1 at install time on systems without a true hardware raid controller. Raid 6 also uses striping, like raid 5, but stores two distinct parity blocks distributed across each member disk. Nov 12, 2014 minimum 3 hard drives are required to create raid 5, but you can add more disks, only if youve a dedicated hardware raid controller with multi ports. Software raid 5 ubuntu grub error 2 solutions experts. This doesnt sound like a highend or traffic server to me, so the performance penalty probably wont be that hard. Is there a way to boot from a software raid 5 array. When i perform a software raid 1 or raid 5 installation on a lan server with several hard disks, i wonder if grub already gets installed on each individual mbr, or if i have to do that manually. R410 w software raid always boots to grub shell after. Here, we are using software raid and mdadm package to create raid. In order to boot properly during the raid setup, we will need to create a temporary grub config file.
Fortunately, it is easy to build a software raid 5 in windows 8. Basically, since xenserver 7 is based on centos 7, you should follow the centos 7 raid conversion guide. How to set up software raid 1 on a running system incl. In the event of a failed disk, these parity blocks are used to reconstruct the data on a replacement disk. Home how to set up software raid1 on a running system incl. Windows 7 has arbitrary restrictions on the available raid levels, and it was impossible to create a level 5 raid without windows server. In most cases i dedicated a raid1 array to the host os and have a separate array for storage. We go the through the process of raid recovery and restoration and learn raid recovery on the command line because it become so.
Once you have completed your partitioning in the main partition disks page select configure software raid select yes select create new md drive select raid type. If the kernel panics because it can not mount the root drive, then the cause is almost certainly that your kernel is missing the mddegradedboot patch see section 4. Xenserver 7 raid1 mdadm after install running system. After first boot, consider executing dpkgreconfigure grub pc or dpkgreconfigure grub efiamd64 on efi systems, and install to all devices. Im trying to setup and install ubuntu on a raid 1 setup. If grub was already installed on the hard drives from a previous version of centos that was running software raid partitions, the system will boot after installing 5. Ive found that the grub boot loader is only installed on the first disk. It should replace many of the unmaintained and outofdate documents out there such as the software raid howto and the linux raid faq. I have my hardwareowned dedicated server hosted in remote datacenter, running centos release 6. Raid contains a group or a set of arrays set of disks. Raid 5 requires 3 or more physical drives, and provides the redundancy of raid 1 combined with the speed and size benefits of raid 0.
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