Xenserver mdadm software raid

For example, a software raid of devhda and devhdb might be accessed through an md device named devmd0. Xenserver 7 raid1 mdadm after install running system server. The grub2 bootloader will be configured in such a way that the system will still be able to boot if one of the hard drives fails no matter which one. The disk io performance loss in xen vms xenserver 5. But from my own expertise, building software raid off different hard drives will sooner or later bite you. How to configure raid 5 after installing xenserver 7. Sep 14, 2009 xenserver doesnt really support fakeraid or software raid. I used the notes from some guy on the citrix forums. A minimal initramfs for assembling md arrays can be created using three files and one directory. This is not normally used to identify an array, but is supported so that the output of mdadm examine scan. Finding almost no concise guide to doing this online and trying to help someone go through this in the simplest manner possible, i thought that it would be good to document the process as we typically dont see xenserver with software raid and when you find guides for that they assume that you are booting from the software raid array as well which adds a lot of unnecessary complication. Xenserver 7 and software raid configuration howtoforge linux. In addition, the price of software raid makes it a very desirable solution. I recently did some performance tests for a couple virtualization technologies.

Also have a cheap fakeraid controller via vt6421 chipset and two seagate 3tb dri. I wish that i had his name so i could give him credit but its not here on the stuff i printed out. Yes, idea of raid1 is that one disk is a copy of another, but this is software raid and it based on partitions. Server peforms a resync for its software raid in defined intervals. Ive modified the commands to what i think works a little better. Jul 29, 2015 the alternative to this problem is configuring the system in software raid1.

The alternative to this problem is configuring the system in software raid1. The sr raid set is on a separate intel raid adapter with separate sas drives. Raid 1 for two drives mdadm create devmd0 l 1 n 2 devsda3 devsdb3 raid. All the processing is done by your cpu and is similar to software raid in that regard.

Xenserver and raid problems im currently managing a xenserver v6. On the steps to follow, devsda are used for the disc where the instalation was made and devsdb for the second disc with the same size. Similarly, in centos systems, it make use of the binary usrsbinraidcheck. We need to install too, but at this time we are stucked on raid software, mdadm. It is used in modern gnulinux distributions in place of older software raid utilities such as raidtools2 or raidtools mdadm is free software maintained by, and ed to, neil brown of suse, and licensed under the terms of version 2 or later of the gnu general public license. Due to the fact that the standard update is a xenserver installation of the new xenserver with virtual machines preservation, with the loss of all the changes that were made manually on the server installed software, changing adding settings through the console, etc.

Oct 06, 2015 in a minute we will see what an alert sent by mdadm looks like. Right away, it saw the raid array and loaded up in about 45 minutes. Xenserver never officially supported software raid. Well, yes, mdadm allows to build software raid from different, nonidentical hard drives. This document describes how to install xenserver 6. You need not rewrite mbr again after rebuild arrays. This guide explains how to set up software raid1 on an already running linux ubuntu 12. Assume, that weve some data saved to logical volume, which is created with raid 10. As expected, we took the dell server out of the box, popped in the usb key for xenserver and loaded it up. Basically, since xenserver 7 is based on centos 7, you should follow the centos 7 raid conversion guide. The usage of mdadm raid was only possible with manual tinkering. The only drawback of mdadm software raid is that you need to know what you are doing, replacing a failed drive is not as simple as pulling the dead drive and popping in the new drive like with.

First we set up the 2nd disk by copying the partition tables whilst enabling a degraded raid on it, then copy data over with custom initrd. For example, in debian, it is based on a linux utility called mdadm, that manages and monitor software raid devices. Linux software raid is damn good and it beats low end raid controllers and usually matches performance of midend ones. Especially because i use uefi with nvme ssd i ended up with no raid. Most modern hardware is more than capable of running mdadm software raid with resources to spare. Historically xenserver does not support software raid outthebox, and this is unchanged in the latest 6. A problem i have encountered is that the xenserver 5. Especially because i use uefi with nvme ssd i ended up with n.

Pls dont link the other thread, it has almost 200 posts. Raid 1 for two drives mdadm create devmd0 l 1 n 2 devsda3 devsdb3 raid 10 for four drives mdadm create devmd0 l 10 n 4 devsda3 devsdb3 devsdc3 devsdd3. The first step is to disable the bios raid and configure the two sata. Xenserver has configured 3 partitions on devsda and left devsdb intact, as shown by the answer file in the example. Oct 05, 2016 xenserver 7 software raid installation issues. Despite the terminology, fake raid via dmraid is a robust software raid implementation that offers a solid system to mirror or stripe data across multiple disks with negligible overhead for any modern system. In principle, it is possible to perform a hot resize for raid partitions, but you must take extra care for your data when doing so. How to manage software raids in linux with mdadm tool. Vmware doesnt support software raid at all to my knowledge, and so its not an option there. Our first dell xenserver was ready to go in less than 2. Here we will use both raid 0 and raid 1 to perform a raid 10 setup with minimum of 4 drives. The mdadm utility can be used to create and manage storage arrays using linuxs software raid capabilities. Installation guides contain sed command usage, which potentially could cause grub errors when boot.

This instruction was written and tested for the xenserver version 7. To simulate an issue with one of the storage devices in the raid array, we will use the manage and setfaulty options as follows. Xenserver 7 raid1 mdadm after install running system. Jul 24, 2017 mdadm grow devmd0 b internal mdadm grow devmd1 b internal mdadm grow devmd2 b internal if your local storage is more than 2tb it will use metadata 1. I have a relatively old server machine which has no sata ports on the motherboard dell precision workstaion 650.

Oct 08, 2015 managing raid devices with mdadm tool. Software volume management evms, lvm and software raid md wrap hardware and other software block devices and give them new names as part of the interface of adding functionality to the storage they manage. Xenserver doesnt really support fakeraid or software raid. Some common tasks, such as assembling all arrays, can be simplified by describing the devices and arrays in this configuration file. The raid1 setup by hetzner is still partially in place. I prefer to build software raid always on identical hard drives, which makes things much more predictable. Once the server comes back from the reboot, start up a software raid volume with mdadm. Sep 02, 2011 a problem i have encountered is that the xenserver 5. Dec 15, 2014 mdadm is an open source, small, fast and free commandline utility implemented in c and designed for maintaining, creating, and monitoring linux md device arrays, popularly known as software raid.

Windows has some form of software raid, but generally it is not recommended and is not easy to boot from. Administrators have great flexibility in coordinating their individual storage devices and creating logical storage devices that have greater performance or redundancy characteristics. Note that if you omit the manage option, mdadm assumes management mode anyway. First, there are operating systems where software raid does not function, or does not function as well as linux mdadm. How to recover data and rebuild failed software raids part 8. Simulating and replacing a failed raid storage device. It is also called intelligent raid on chip iroc or software raid and it is built into the firmware of the controller. Convert xenserver installation to software raid1 technicus. Import software raid and storage repository on it maybe reinstall software raid. Mdadm raid is supported for both, storage repositores as well as the base system.

Our first dell xenserver was ready to go in less than 2 hours time from unboxing to complete software setup. As with level this is mainly for compatibility with the output of mdadm examine. Finally, add the new partitions to your raid devices i think the remove step is necessary since the partitions are listed as failed parts of the current devices. The esxi is not working with software raid, so i want to switch to proxmox or citrix xenserver. Hey guys, are you looking for on how to keep track your xenserver status of raid disk and want to make it in a daily checking and alerting by send email. The installation iso supports the creation of mdadm based software raids. In case you initialized raid before, you should stop any devmd devices in order to go further with installation. The mdadm 8 tool supports resizing only for software raid levels 1, 4, 5, and 6. Dear, someone here has already installer xenserver 7.

Apr 14, 2015 hey guys, are you looking for on how to keep track your xenserver status of raid disk and want to make it in a daily checking and alerting by send email. These raid levels provide disk fault tolerance so that one component partition can be removed at a time for resizing. To begin you must to know at least basic centos command. You cannot complete the steps in this post if your xenserver. When its done on all three arrays, copy the raid setup to etc mdadm. Stop here and reboot your xenserver box to pick up the new partition changes. The highlighted text in the previous image shows the basic syntax to manage raids. There are plenty of them in the internet, but the bottom point is this. We need to install too, but at this time we are stucked on raid software, mdadm configuration. How to manage software raids in linux with mdadm tool part 9. Just for an example, if we are saving a data apple this will be saved under all 4 disk by this following method. How to build your own xenserver with raid sms it group.