Posted: Fri Aug 20, 2010 22:16 Post subject: Raid0 on RT-N16 Help
I have an Asus RT-N16 with the latest version of DD-WRT on it. I purchased two 1TB USB hard drives and am trying to configure them in a raid0 array on this router. I installed mdadm via ipkg-opt and haev tried to configure raid directly on the router via CLI. I partitioned the drives with linux-raid autodetect file system and then proceeded to mdadm --create /dev/md0
1. When I try to create the array with the above command I get mdadm: can't resolve symbol '__ctype_b_loc'
2. This is likely cause /dev/ is not writable so I mknod /dev/md0 b 9 4 2>/dev/null and try to create the array again. This time I get mdadm --create /dev/md0
mdadm: /dev/md0 is not a block device.
3. I created the array with these two drives on another linux machine hoping it would some how help mdadm scan and detect the array on the RT-N16 still no go.
Does anyone have any other things they can help with? I don't see why mdadm can be installed when your unable to create a device for mdadm to manage.
I am about to drop $82 on a group of very well selected USB hubs and various drive enclosures. My desire is to use mdadm to create some type of RAID array where the storage of all the drives is merged and can be shared with SAMBA in an easier way... vs monitoring the size of each directory on each device and ensuring they all have sufficient space. or running into space errors when others try using my shared storage spaces over SAMBA. Annoying!!
I have installed mdadm and am reading up on the documentation... doing some research which lead me to your post. It seems no one else has even tried using mdadm .. or at least isnt talking about it. (only this guy who asked but didnt get any answer..)
I shall monitor this thread with you and weigh in when I get my equipment and attempt setting it up. I am using a Netgear WNR3500L
:?: I'm gonna be angry if i cant get RAID working .. especially because I will have to move all drives back into that old crappy intel windows box I was maintaining , that consumes 250 watts just serving up all my shares. Using DD-WRT, samba3, and some enclosures .. I hope to bring that down to <50 watts.
P.S. I received your can't resolve symbol '__ctype_b_loc' error .. but after installing and when trying to use man with man-pages. I did research and its apparently related to some locale issues. All of which will require a recompile in order to resolve (meanign the authors of these programs have to do them). At least that is my understanding ... sounds like we might be shit out of luck.
I also received your "not a block device" error message, but when trying to move/permanently relocate JFFS off the flash of the router and onto the JFFS partition I created. Couldnt get that to stick so I gave up for now.
I wonder if these issues are not due to my own "beginner" status with linux (I am a fast learner...) but instead due to errors during compile of the programs we are trying to use....
I have ran into this issue compiling applications to run on DD-WRT, there is nothing much you can do short of re-compiling either the kernel or uclibc (I can't remember) to support locales.
This may still not function as you hope, you should really get a multi-bay NAS and save yourself the headache IMHO.
From reading more it appears you may be able to re-compile the offending application itself if your into that sort of thing, I guess if it is important enough you can learn _________________ Eko Builds
i have had zero luck with this and got fed up. I've just made a share and shared the drives via samba. Getting a NAS is not ideal for me. I'm looking to consume the least amount of power while still having the largest capacity possible. Using laptop USB 1TB drives seems to be the best way to do this. Having an extra NAS is more power, typically more money, and typically 2.5" drive size.
I was going to try OpenWRT but I don't have anymore time to tinker with this.
If someone finds a solution then great, post it and ill try it also on a spare router.
I'm looking to consume the least amount of power while still having the largest capacity possible. Using laptop USB 1TB drives seems to be the best way to do this. Having an extra NAS is more power, typically more money, and typically 2.5" drive size.
Since you have 3.5" drives and are concerned with power consumption and cost, have a look at this Dlink DNS-321 from Newegg ($123.98 shipped) with a possible $20.00 off mail-in for a total cost of ($103.98 shipped). At maximum the unit uses:
+ Normal mode: 29.67W
+ Sleep mode: 4.67W
If you do the headache to dollar ratio I believe you come out ahead with something like this over a router doing full NAS duties. _________________ Eko Builds
yeah I was considering a seperate piece of hardware, but it didnt make sense for me since I already have the windoze PC which works fine for my serving.
Also the windoze pc will take USB drives, IDE, Sata, and/or Firewire and not care at all.
Hardware NAS products are usually only SATA... a significant deal breaker for me as I'm trying to make use of the hardware storage I have already (2 IDE drives, 1 USB, various USB flash drives, 1 SATA drive).
Ideally I just want a script that checks storage space of each drive and silently copies the file to the one with the most, still allowing linux to see just one directory covering all drives. IDK if this exists and figured software raid was the closest I could get.
Since this is on subject .. Are there any OTHER ways (aside from RAID) of storing data across multiple disks, whether in windows or linux / DD-WRT?
That may be a better option for me than additional hardware. Maybe I should cancel my enclosure / hub order ....
LVM lets you glue together multiple partitions. It's pretty normal on normal linux systems don't know how's about dd-wrt linux an LVM. The advantage over raid is that you don't need same partition size and you can shrink/extend an LVM-Partition online.
You can use rsync to do what you wish, use the hub and USB attached storage along with rsync from optware.
There may be an issue with using multiple LUN's still, I am unsure. It will work although you may have to do a bit of manual installation (terminal work).
I didn't fully read your post, you can mount a directory into a subdirectory to be able to 'see' all storage from a single location. Meaning you could 'mount --bind' to 'merge' one storage location into another. _________________ Eko Builds
YES! I'm not interested in the RAID backup features, nor their consumption of storage space.
I will certainly be checking out LVM.
I am already somewhat familiar with rsync, but didnt know it had any storage space knowledge feature(s). I will read the docs in more depth.
Thank you both for the pointers! Most of the time for me (a newborn newbie) the problem is finding the program / method I need to look at to accomplish what I want. My googlefu needs more refinment and I hate that this forum wont let you search in TOPIC TITLE only!
In any case, thank you both!
Maybe I'll consider learning recompiling in the future .. but like you say. probably not worth the headache.
Goodbye mdadm. I can probably figure something out from here.