Red Hat / Fedora :: Managing Software Raid Arrays?
Jun 10, 2011
With mdadm was only able to add a new drive to the using the --force function. I do not feel comfortable with using the function that way though. When I remove a disk in VMWare, it perfectly says that the drive is lost and the array is degraded (mdadm --detail /dev/md0). Although after re-adding the drive, it immediately shows device as busy for both mdadm and sfdisk when I don't use --force.
Recovery and repairation of degraded array worked fine with sfdisk --force, mdadm --add --force, it automatically started recovering and took not so long. What are best practises to manage software raid-1 arrays?
With mdadm was only able to add a new drive to the using the --force function. I do not feel comfortable with using the function that way though.
When I remove a disk in VMWare, it perfectly says that the drive is lost and the array is degraded (mdadm --detail /dev/md0). Although after re-adding the drive, it immediately shows device as busy for both mdadm and sfdisk when I don't use --force.
Recovery and repairation of degraded array worked fine with sfdisk --force, mdadm --add --force, it automatically started recovering and took not so long.
What are best practises to manage software raid-1 arrays?
Have a customer who is due for a new system. AS they just renewed their RHEL entitlement, they plan on ordering a Dell server without a OS preload. Two questions:
- Will RH let them download RHEL6 just by maintaining the entitlement when their current version is RHEL 3?
- The server will have two RAID arrays - one intended for /home, one for "everything else". As I've never done a clean load with two arrays, how do I select what file systems go on which array?
I am in a situation where I am stuck with a LVM cleanup process. Although I know a lot about AIX LVM , but this is first time I am working with Linux LVM2. Problem is that I created two RAID arrays on storage, which appeared as mpath0 & mpath1 devices (multipath) on RHEL. I created logical volumes and volume groups and every thing was fine till I decided to clean the storage arrays and ran following script:
#!/bin/sh cat /scripts/numbers | while read numbers do lvremove -f /dev/vg$numbers/lv_vg$numbers vgremove -f vg$numbers pvremove -f /dev/mapper/mpath$numbersp1 done
Please note that numbers was a file in same directory, having numbers 1 and 2 in separate line. Scripts worked well and i was able to delete definitions properly (however I now think I missed one parted command to remove the partition definition from mpath device. When I created three new arrays, I got devices from mpath2 to mpath5 on linux and then I created vg0 to vg2. By mistake, I ran above script again for cleanup purpose and now I got following error message
Cant remove physical volume /dev/mapper/mpath2p1 of volume group vg0 without ff[/B]
Now after doing mind search, I now realize that I have messed up (particularly because mpath devices did not map in sequence to vg devices and mapping was like mpath2 --- to ---- vg0 and onwards). Now how I can cleanup the lvm definitions? should i go for pvremove -ff flag or investigate further? I am not concerned about data, I just want to cleanup these pv/vg/lv/mpath definations so that lvm can be cleaned up properly and I can start over with new raid arrays from storage?
I'm trying to setup a RAID 5 array of 3x2TB drives and noticed that, besides having a faulty drive listed, I keep getting what looks like two separate arrays defined. I've setup the array using the following : sudo mdadm --create /dev/md01 --verbose --chunk=64 --level=5 --raid-devices=3 /dev/sdb /dev/sdc /dev/sde
So I've defined it as md01, or so I think. However, looking in the Disk Utility the array is listed as md1 (degraded) instead. Sure enough I get :cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md1 : active raid5 sde[3](F) sdc[1] sdb[0] 3907028992 blocks level 5, 64k chunk, algorithm 2 [3/2] [UU_]
So I tried getting info from mdadm on both md01 and md1 :user@al9000:~$ sudo mdadm --detail /dev/md1 /dev/md1: Version : 00.90 Creation Time : Sun Jan 9 10:51:21 2011 Raid Level : raid5 ......
Is this normal? I've tried using mdadm to --stop then --remove both arrays and then start from scratch but I end up in the same place. I'm just getting my feet wet with this so perhaps I'm missing some fundamentals here. I think the drive fault is a separate issue, strange since the Disk Utility says the drive is healthy and I'm running the self test now. Perhaps a bad cable is my next check...
I have created software raid 5 configurations on the second harddrive its working fine and i have edited fstab file for auto mounting when it reboot but when i reboot the computer raid doesn't work i have to re-create the arrays by typing "mdadm --create" command again and mount again manually ,is there anywhere i can do this once without retyping the commands again after rebooting and i am also using redhat 5
what do I have:2x 150GB drives (sda) on a raid card (raid 1)for the OS (slack 13.37)2x 2TB drives (sdb) on that same raid card (raid 1, too)2x 1.5TB drives (sdc,sdd) directly attached to MoBo2x 750GB drives (sde,sdf) attached to MoBo too.if i got about it the normal way, i'd create softRAID 1 out of the the 1.5TB and the 750GB drives and LVM all the data arrays (2TB+1.5TB+750GB) to get a unified disk.If I use btrfs will I be able to do the same? mean I have read how to create raid arrays with mkfs.btrfs and that some lvm capability is incorporated in the filesystem. but will it understand what I want it to do, if i just say
I have never preformed a rebuild of an RAID array. I am collecting resources, which details how to build an RAID 5 array when one drive has failed. Does the BIOS on the RAID controller card start to rebuild the data on the new drive once it is installed?
I have two SAS RAID controller cards in a Dell server in slots 2 & 3, both with an array hanging off them. I went to install a third card into slot 1, but then when it boots it says two of my sd's have bad magic number in the super-block and it wants me to create an alternative one, which I don't want to do. If i remove the new card, the server boots perfectly like it did before I added the new card. Is the new card trying to control stuff that isn't hooked up to it because its in slot 1, so its confusing RHEL?
So I have a system that is about 6 years old running Redhat 7.2 that is supporting a very old app that cannot be replaced at the moment. The jbod has 7 Raid1 arrays in it, 6 of which are for database storage and another for the OS storage. We've recently run into some bad slowdowns and drive failures causing nearly a week in downtime. Apparently none of the people involved, including the so-called hardware experts could really shed any light on the matter. Out of curiosity I ran iostat one day for a while and saw numbers similar to below:
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Some of these kinda weird me out, especially the disk utilization and the corresponding low data transfer. I'm not a disk IO expert so if there are any gurus out there willing to help explain what it is I'm seeing here. As a side note, the system is back up and running it just runs sluggish and neither the database folks nor the hardware guys can make heads or tails of it. Ive sent them the same graphs from iostat but so far no response.
How do I determine what graphics card I am using in Linux? In windows it's no problem, but I don't know how to determine such things as a) what hardware am I using? and b) what driver am I using? After determining which hardware my display is using, what is the best way to manage the drivers to ensure i'm using the most up to date version?
I've been banging my head over this Linux assignment for a few hours now and just can't figure out a proper solution. Basically we're acting as a system admin for a fictional company, and we have to assign permissions to various directories based on groups. The Executive Group (exec) -exec-normal, exec-secure directories The Project Management Group (pm) The Design Group (design) -preliminary design (des-prelim) and Revised design (des-rev) directories. The End Users group (users) the following users must be made: exec1, exec2, pm1, pm2, des1, des2 ,user1, user2 all files from each group are stored in /home/docs/ The directory tree is as such /home/docs/{exec-normal,exec-secure,des-prelim,des-rev,share}
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So what I thought of and tried to do was this: since people of different groups need rwx on same directories I decided to group those people up into their own groups and assign that group to the given directory. So for example design(des1,des2) and pm(pm1,pm2) both need to modify files in /home/docs/des-rev therefore I grouped these 4 users together in a group called GroupRev and made GroupRev the owner of the /home/docs/des-rev/ directory with the permissions drwxrws--- and this works for those users and all but 'users(user1,user2)' need to be able to view docsuments in /home/docs/des-rev as well and if I set the others permission then the WORLD has those permissions. and this problem is consistent in my planning. With this idea I grouped exec1, exec2 into GroupExec and des1, des2, user1, user2 into GroupPrelim and assigned the groups to the proper directories.
so currently my permissions are pretty much the same for each directory drwxrws--- and with this each user can modify files in directories they're supposed to.. but if users from another group need to view documents in another groups directory, they can't. I can't use ACL's and must do it this way. I guess all I'm really asking for here is a push in the right direction.
I'm often switching between the following three languages to check spelling in evolution, firefox and gnote:
English / United States Dutch / Netherlands Croatian / Croatia
The problem is that the language list is huge, what makes switching between the languages difficult. There are more than 20 types of English spelling and 3 Duch spellings (see the screen-shot).
I would like to configure this language list, so that only the relevant languages are displayed.
I've tried to install Fedora 11, both 32 and 64 on my main machine.It could not install as it stops on the first install window. I've already filed a bug but really haven't seen any feed back yet.The bug has something to do with Anaconda and the Raid array but I really can't tell.
I have an Intel Board (see signature). I am running intel raid software under W7 currently.It works fine. But, I'm wondering, when I attempt to install F!!, is my current raid set-up causing problems? Do I need to get rid of the intel raid software and use a Fedor/Linux raid program to manage the raid array??
I have just installed Fedora 14 on my Acer Extensa 4220. I am having trouble finding way to manage the built-in webcam: I surfed all the options on the menus and could not find the suitable application to do that.
Could any RAID gurus kindly assist me on the following RAID-5 issue?I have an mdadm-created RAID5 array consisting of 4 discs. One of the discs was dropping out, so I decided to replace it. Somehow, this went terribly wrong and I succeeded in marking two of the drives as faulty, and the re-adding them as spare.
Now the array is (logically) no longer able to start:
mdadm: Not enough devices to start the array.Degraded and can't create RAID ,auto stop RAID [md1]
Code: mdadm --create --assume-clean --level=5 --raid-devices=4 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2 As I don't want to ruin the maybe small chance I have left to rescue my data, I would like to hear the input of this wise community.
I have a problem on a program,the problem take a very long time when i try to add two big arrays element by elementI know that matlab make adding vectors more faster than adding element by element but I don't know how!!!do any body knew how matlab make vectors operations more faster than element by element???I want to make my calculation more faster because the program is very big
I was reading Kernighan Ritchie book chapter 4 which deals with character pointers.I am not able to understand following different type of declarations
Code: char aname[][15] = { "Illegal month", "Jan", "Feb", "Mar" }; char amessage[] = "now is the time";
need to process files within multiple directories and transfer these to a remote server. What I had in mind was to use arrays for this; code pasted below (explains it better):
Code: #set the arrays array_A=( fileA* pathtodestA hostA passwordA )
I'm looking for a program to manage my music, and if I keep using Banshee, I'm likely to break something in my house. All I want to do is edit file tags (like genre, artist, and album title) - but it won't let me do that. I can't edit the files directly - first I have to get them into the "library", and in order to do that, I can't drag and drop them - it forces me to actually open up the files (which plays them, and sticks them smack into the middle of the "library", and I then have to go searching/scrolling through the whole thing in order to locate them and then finally edit them). And after all this, spending like 4 hours doing all this, I find out that IT DIDN'T ACTUALLY EDIT THE FILES. It edited them in its own mind - for the duration that they were in the "library" - but it didn't make a change to the actual files.
Is there a way to have grub2 managing two installations from ubuntu on the same pc ?I have two partitions, one with karmic, another with lucid. Grub is detecting automatically the two or more kernels, but assigning them to the same root partition.Is there a way to make update-grub, detecting lucid kernel, and assigning it automatically to lucid partition, and the same for karmic ?It seems, that os-prober, detects the lucid installation from karmic, and print the correct corresponding partition on the screen, but in the config file, the root partition is the wrong one, and os-prober doesn't detect karmic...
What I've noticed recently in file managing is that sometimes one file might fit multiple categories yet you must fit it into just one (without linking the file). It is most essential when managing an ebook library or a project library (for example have I placed a particular script under PHP_Scripts folder or CMS folder... I tend to forget).
What I'm looking for is a Tag categorization type of management for files. The PS3 file manager is a good example for this since I could make it generate folders by the artist's name, the year etc. for music files, then I would just navigate to the particular folder to find what I was looking for. Now my question is if such thing already exists as a nautilus extension or as a stand alone application... If not would you guys think it would be worth creating? If you do should it be approached as:
* A Nautilus extension? * or as a python script? For example one that creates a folder with folders in it, made up from the [nautilus] tags of the files you want to browse, then creates links of all the files [you wanted to browse] automatically to the appropriate tag folder[s] generated.
I finished a program that connects to a remote server and does some stuff there for a while. What I want to do is to run several instances of the program to have different connections at the same time, and to be able to manage those processes automatically (for example, if the connection stops, detect it and reconect).
I guess I will have to use the pid of the processes and handle them somehow but I dont really know what to do because I haven't used c++ in a while and I never went that deep. All this will be running in suse, debian and/or yellowdog distros Maybe there's a tutorial or you guys know some tool that i can use,
I'm having a little issue managing my iphone on archlinux+kde. This is the only way I got it to sync.
sudo killall usbmuxd sudo usbmuxd -f -v
And then the only program that recognices the device is Clementine and it works quite fine. What I'd like to do is to make that automaticaly, so I wouldn't have to do it everytime i turn on my computer.
Currently i using webmin,but it missing some important things like $variable -where $variable would be automatically replaced with added domain,and it's kind a strange since plugin for managing other dns server on webmin does that. Also i was not able to generate 100% correct all records,only partial,which make it useless since i was need to fully replace it anyway.So can someone recommend any script/tools for it?I would be even happy with combination of batch tools(which might be even best solution since then i would not need to bother with installing script). How my dns records look:
PHP Code: $ttl 38400 @ IN SOA ns1.nameserver.com. root.localhost. ( 12520521667 7200 7200 604800
I reckon I waste several tens of gigabytes of storage by holding unwanted copies of personal data and media files over very many partitions. Sometimes they will have identical names, dates and sizes. Other times they may be slightly different in terms of metadata but nonetheless essentially identical in respect of content. It is becoming a nightmare. Any suggestions for how best to get rid of these unwanted files?
I have centos 5.4 installed (2.6.18-128.2.1.el5 #1 SMP Tue Jul 14 06:36:37 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux), and I am using WHM/Cpanel to manage my server. I am looking for a GUI utility, so I can graphically manage users/groups.
Is there a way to compare an array in a while conditions?
I have one array that contains the results of some search and if the script has found all the items, then it should stop, so my idea is to have a while loop � la:
