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NAS for office server?

By cookiedude
Mar 21, 2012
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  1. Hi all

    So the situation is thus; we are looking into getting a new server for our office (currently all individual desktops and laptops!) and have been given a quote that has come in considerably higher than we'd anticipated. Part of this is due to the addition of a tape auto-loader as a backup device, which is coming in at £2730 (including 20 tapes)! The benefits we've been given for this are tapes being more robust (especially if being take off site) and more secure than hard drives, but I have a concern at how accessible the data is should we need to resort to accessing the backup.

    This got me to thinking would a NAS device (or multiple?) with hot-swappable drives used in a similar way provide the same functionality as the auto-loader, but at a much cheaper cost? And if so, what would people recommend for this?

    I am fairly well versed on consumer devices from the likes of Synology and we already have a Lacie NAS in the office for general file storage (though it's not been that relaible) but I have no experience with multiple bay, hot-swappable models. Is there a particular brand I should look at that offer more commercial devices or would a 4-bay Synology be fine?

    Thanks in advance :grinthumb
  2. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    You are into the area of planning called "Business Continuation"; how do you continue
    when there are different levels of failure?

    Consider (list in order of difficulty):
    1. drive or system fails
    2. building becomes unusable (fire / floor/ storm)
    3. city takes a tornado / hurricane hit
    4. county / state looses power

    In addition, tapes per se are frail media and for long term storage, need humidity and temp controlled storage - - and regardless, the magnetic info degrades and/or 'imprints' from one layer adjcent to another. We saw this with IBM and tapes stored at Iron Mountain.

    Local backups (ie store onsite) work well for all variations of (1) and off-site storage
    only delays the recovery time.

    (2) will likely wipeout all local backups (tape or otherwise) and is why off-site is necessary.

    (3+4) makes the point that off-site storage is viable ONLY when it is outside the area of the disaster.

    IMO, tape is a dead media - - what a mess if you need to use a backup set and find that after mounting several tapes in a restore you find that the nTH tape is unreadable :OUCH:

    a) you ask the right question; which NAS systems are most reliable?
    Google for "review scsi nas with hotswap".

    b) get a SCSI enclosure with several bays and implement Raid-1 (mirrored)
    with auto-rebuild to avoid hard stopping the system while a new drive is brought online.

    c) determine the degree of effort to recover 'lost data'. It is impractical to take
    a drive offline every day, so what period can you tolerate between HD rotations?
    (suggest one per week + one per month = 8 drive in rotation pool).
    Then keep last weeks drive local and all else offsite.

    my $0.02
  3. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    Wow, comprehensive, thanks :)

    For us the most important feature of the backup system would be to allow us to access our data quickly should the the server suffer a major catastrophe! And I guess it would have to be something pretty severe to cause a complete failure with the server drives as they will be RAID configured (3Tb useable) and hot-swappable.

    We plan to utilise off-site remote backup through the company providing the server at a later date (we're looking into having Fibre installed as our ADSL just can't handle this) so there is a need for an interim off-site backup solution and in the proposed system this will be removing tapes/HDD from the premises and storing them... which could prove a logistical nightmare, but only option at the moment :(

    I'll have a look at the SCSI NAS enclosures but I have a feeling they're going to be expensive too?? Would it be viable to use a standard SATA enclosure allowing time for a full backup of the server and then utilising a real time incremental backup? Or would this be too slow to cope with a server configuration?

    Regarding drive rotation, if I have 4 drives in RAID 1, would I be able to remove 1 or 2 drives per day/week (depending on need) to store offsite? I think any more than this and cost could become prohibitive!

    FYI - Maximum users 20. Most of the server traffic will be from 6-8 designers (on PCs) often working with quite large file sizes. Other staff (including PMs and MDs) will primarily use it just to backup their Macbooks and access project files as and when necessary.
  4. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    not all Hotswap == Hotswap. A SCSI card with full Raid-x support and independent volume recovery is worth $$$$$$, in time & procedural savings.
    Think this over carefully - - then do it again. Compare ANY Raid-x solution side-by-side
    to make sure you know what you get vs. what you just gave up!
    Location of user files and what is or is not backed up is critical.
    With a Windows Server as the primary data server, the NAS (or offsite direct backup service) is the focal point - - NOT the users PCs.
    With user profiles on the Windows Server, the PCs become immaterial.
    Manage the WS / NAS and you've covered the bases.

    DO NOT attempt nor assume that you can backup a PC and restore it later in time if it has a melt-down.
    You are protecting the users data (eg \Documents & Settings\%userprofile%\*) and NOT the bootable hardware+os+programs+data.

    btw: use differential over incremental - - saves media+time & complexity.

    keep asking the question, "what does it cost me (time, money, effort, staffing) if I don't have what I need when I need it."

    Every GOOD disaster plan has at least one simulated recovery walk thru.
    Joe Manager says:

    1) "database X just crashed - - recite every step and resource necessary to recover it"

    2) "server X just had a hardware failure and needs to be totally replaced (cpu, OS+App software and all peripherals"; a) what do we order b) how long for it to arrive, and c) what is the end-to-end time to bring it online?"

    3) Manager goes into the server room, yanks a hotswap drive out its slot and walks back to his office (FOR REAL!!!) - - document the steps and time to restore the RAID to fully protected operational status.

    4) worst case; assume the building is now burnt to the ground.
    Document another facility not in this County and determine;
    a) who will go to the new facility to start the new site
    b) how / where to get the hardware eg (2) above
    c) where to they get the written procedures, configuration data and access to the off-site backups?

    IF you and your manager are comfortable with the results above, THEN & ONLY THEN and you take pride in your efforts and give a dinner to the staff for a job well done.

    Best Wishes.
  5. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    Thank you so much for yet another comprehensive response, really appreciate it.

    Is there a particular specification/feature set I should look out for in a RAID solution? If Hotswap doesn't always mean Hotswap, what should I look for to identify one over the other? If I were to buy something now I would look for RAID 1 across at least 4 drives (all hotswap) and read/write values, should I be looking at more than that?

    Totally appreciate all of this, I just wish other people in the office did too :) Our aim is to have all data backed up to the server as often as possible (the PMs are often out of the office so their files can't be done every day). I was only pointing out the user base in case that type of scenario might affect how we set up the system, particularly with regard to backup efficiency. Obviously if a PC/Mac fails then there will be downtime associated with this, but at least the data is safe :) What would cause a major problem would be downtime for accessing backup data should the server fail.

    Thanks for the tip :grinthumb
  6. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    btw: NAS is just the interface (ie network ) to an enclosure with HDs.
    The 'guts' are the Raid-x implementation which is the target device for fail-safe backups.

    In addition, you need a secondary backup of the Raid itself;
    Raid-1 is a FAIL-SAFE concept, not a backup concept. It can be used that way
    as long as you control it and don't make rash assumptions.

    A good SCSI card in a 'server class machine' can provide the Raid-x too.

    what is hotswapping?

    Software vs Hardware Raid

    Hot-Standby

    I'm surffing to find the answer to:
  7. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    The critical term is 'rebuild' and you need to have a 'hotspare'.

    ALL Raid-1x cards/enclosures will provide a means to rebuild the broken mirror;
    a) manual rebuild; take the raid offline, swap the HD and rebuild. place online when done.
    b) auto rebuild; with a hotspare, the autorebuild just takes place.
    w/o the hotspare, user dismounts failed HD, hotswaps the new drive and autorebuild begins.

    choice (a) is silly imo. WHY go to all this effort and not keep the system running and the storage online?????

    see the issues here
  8. Sunny87

    Sunny87 TS Enthusiast Posts: 120   +11

    Cloud Storage? (Amazon offer some good deals) I would also like to point out that by adding servers and indeed the now need to have a server room with air conditioning you are also going to need a technician to manage the servers and networked desk stations.
    NAS I would not recommend, it's okay for home or small office's but it does not suffice for the bigger tasks.

    If you wish to have onsite backup then SAN plus Quantum tapes is going to be your best option but SAN is or can be extremely expensive, SAN plus Cloud storage may be a better option as you will have the added knowledge that should you need to do a quick work restore you can do it in house, but if the entire server room is destroyed you have your cloud backup.
  9. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    @JoBeard,

    Would a more redundant RAID not be better in this scenario? I mean RAID 1 is great as a fail safe (I use it myself), but using it in a production environment with more than a couple of users and the possibility of failure, is it not going to be better to use RAID 6 with a couple of hot spares? -- genuine curiosity here, as I'm planning on moving to RAID 6 shortly myself.

    That said, RAID 1 with 8 "spares" to enable complete offsite storage definitely sounds a wise idea, and removes the requirement to cloud store any confidential data, or the necessity to pipe it through a high speed fibre connection between the two.

    @CookieDude,

    I have one observation -- does that quote include support as well, and who will be managing it if you go your own route?

    I definitely agree you want a setup that automatically rebuilds itself when required. You'll always find a hard disk failure occurs when you need it most, and not having that feature will result in your entire filesystem offline until the new disk is copied across. Personally, I'd use the hot spare method, purely because the rebuild will be immediate without any physical intervention -- ideal if it fails late at night, or out of hours.

    Its an important point though, because in the event of a disk failure you need to get the disk replaced and the files mirrored as soon as physically possible. Having the hot spare will enable that to take place immediately, as your data is vulnerable whilst down to one single disk.

    Realistically you are going to need 3x disks for the RAID (2 RAID 1 + 1 hot spare), plus 8x disks for the backups, plus at least 1-2 spares for immediate replacement in the RAID. You also need the disks to be of the same spindle speed, memory buffer and capacity for the best results -- some people recommend you use different manufacturers disks to ensure you do not end up with multiple instantaneous failures if you get a bad batch.

    It isn't cheap, but it does mean you can likely avoid off-site cloud storage as a means of backup, which takes away the requirement for fibre being installed if your current ADSL is adequate.
  10. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    The raid types which implement parity, imo just add expense and only assist during the recovery process (should be the least frequent activity) - - so I'm no fan of raid 5,6. If I need higher i/o rates, I would go with raid-10.

    Jury is still out that the Cloud is really viable and Cloud Backups - - not me!! If I have the responsibility for a business system, I'm not going to delegate the Disaster Recovery to a man behind a curtain (aka the Wizard of Oz) and I have to call someone in the Philippines to get service.

    We started with NAS, but quickly dove into Raid which is the real issue (see post#6). BTW: Personally I am torn twiz accessing the Raid via NAS and a good SCSI card in a server and the Raid being shared to all. The latter would be my choice as it reduces the number of components that could fail and SCSI Raid controllers have been around much longer. Also consider, if the NAS enclosure is the failing component - - how do you recover? You have to have a second one in the closet :(

    (this is vendor specific but the analysis is great imo):::
    see full descriptions and illustrations for each of these, just CLICK on the raid level of your interest.
  11. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    Thanks all for your input, proving very helpful for the most part. My knowledge of Servers, NAS, RAID, etc has increased substantially in the last week :) I think now would be a good moment to simplify exactly what we're looking for. The company that provided the quote are suggesting a system like this:

    Server:
    HP ProLiant sever (6x1TB/RAID5/3GB useable)
    Backup:
    NEO200S SAS Autoloader (Symantec Backup Exec 2010 for daily backup)

    So there will be redundancy built into the server, and we also have on-site tape backup. However, we also need the backup data to be accessible over the network should the server go down (and only if the server goes down!). So the question is would a NAS be the correct solution here rather than tape or is there a similar storage option available. Criteria to consider:

    Network accessible
    Built in storage redundancy (I reckon RAID 1, 5+1 or 10 would be the way to go here?) to further protect the backup
    Must have it's own power supply
    Hotswap drives to allow the option of cycling drives and storing off-site

    I hope this helps to make my situation clearer? You've provided great insight into the technical/feature requirements but I'm still not clear on what our best option would be. I'm happy with the server solution we've been offered, so I'm more concerned with finding the best backup solution for our needs.

    I have just posed the question about support. I checked the prices for that hardware online and they're pretty similar so I expect support to be additional (which I'm surprised at as we definitely discussed including it). Whichever way we choose to go we still intend to use this company for installation and support.
    Would utilising RAID 1 across 4/8 bays offer a similar level of protection to having a hot spare? Would a NAS with Hotspare facility still offer the flexibility to hotswap drives?

    As mentioned our broadband is poor so this option is not really viable (especially when we're considering a minimum of 2TBs of data!). To echo Jobeard's comments I wouldn't want to trust such a system just yet. Also, we do plan to introduce a full remote off-site data backup facility as/when we get fibre installed. As for now the best option to us is to physically store drives/tapes off-site (though we haven't quite worked out the logistics of this yet!).

    So just to be clear remote backup is not an option, I am looking for the most flexible on-site hardware based backup system I can get :)

    Here's one that might fit the bill, please let me know your thoughts:

    http://www.synology.com/us/products/DS1511 /index.php
     
  12. Sunny87

    Sunny87 TS Enthusiast Posts: 120   +11


    As Cloud is not a solution for you I would suggest then going with a SAN and the auto loader(there not as cool as they sound or as auto) I would say try to get it so that backup exec backs up over night to the SAN and then the SAN is backed up by the tapes, this means that the tapes can run during daytime use with out any network slow down as the server will not be being backed up but the SAN, this is a similar setup to what I did in a school but the backup was SAN to SAN to tape so three backups two onsite one offsite.

    Have a look at theses http://www.ebuyer.com/344260-drobo-8tb-san-storage-for-business-dr-b800i-2a31-d04 they do a 24TB version for not much more than the 8TB version.
  13. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    So it already has RAID 5, the only change I would make here is the inclusion (buy the disk yourself if they're not competitive) of another 1TB disk, to run as a "hot spare" assuming this setup isn't already using it.

    The reason for that is a RAID 5 array can handle one single disk failure without data loss. When a single disk fails the data on the array is at serious risk of complete loss until the failed disk has been replaced and re-populated with data.

    Running a hot spare will (hardware dependant) enable that process to take place automatically and more importantly, immediately upon disk failure. You then simply swap out the failed disk and it remains there as a hot spare until another disk fails.

    A NAS would be an ideal solution in this case. But whether you make backups with a tape drive, or a RAID NAS solution, the more crucial thing is to verify every backup to ensure it is valid.

    I personally prefer drives to tapes, because tapes wear out, and disks generally speaking last ages if well cared for. I'm also speaking from my personal experience in a home environment, not a business environment.

    A NAS would enable you to deploy immediately the data your server contained, if for some reason your server was unavailable. A RAID 1 NAS using two 3TB hard disks would offer you the capacity of your servers RAID 5 for storage, with the additional redundancy of having the data mirrored over two disks.

    RAID 1 can tolerate one disk failure. Like RAID 5, it is vulnerable between a disk failing and the data being written to a new disk.

    The idea behind a hot spare is simply to have a disk sat waiting to replace any single disk that fails, and automatically re-populate the data of the failed disk. It also means that your data remains vulnerable for less time as it doesn't need human intervention in order to resolve the problem. You then replace the failed disk, and as I understand it, the new disk becomes the hot spare until another disk fails.

    You certainly wouldn't want to keep all three backups on the one site, that's for sure. Also, you need to factor in the time to verify backups. It is crucial that all backups are verified as valid, because invalid backups will not help you restore lost data in the event of a total failure at your site of business.

    Lastly, using the RAID on the server, a RAID on a NAS and a tape drive would offer you a good solution for data security, as long as the tapes were kept offsite. The NAS could also be kept offsite if required, and the data sent securely and encrypted by SFTP between the two locations during backups.

    I would also wait for JoBeard's thoughts as well, before making any decisions.
  14. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    Wow, they're quite expensive! Couldn't find the 24TB version on there, but I guess it's the same unit just with bigger hard drives?? What is the benefit of a SAN over a NAS? They seem like very similar beasts?

    With everything I've been reading I was thinking this would be a good idea too. Is it possible to have 2 hotspares with RAID 5? Given hard drives are relatively cheap I reckon we're best to cover ourselves as much as possible, where possible :)

    Would this be something I could set the backup software to handle or does it require physically checking the data on the drives? If we were to plump for using RAID 1 in the NAS is there a limit to how many drives can be mirrored? Eg, if we get a 5 bay NAS can we use 5 3TB drives all mirroring data? This way we could rotate disks more often and even consider multiple off-site storage :)

    I think the "extra" backup using tape may have to wait due to cost but certainly we will need something along those lines at some point. Out of curiosity, if we had a remote backup (whether tape or drive based) what kind of upload speeds would be required for this to work based on NAS backing up server overnight, remote solution backing up NAS during the day? Or would this massively affect our companies broadband bandwidth? Currently we get around 3Mb download and 700Kb upload (which is rubbish!).
  15. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    I'll address some secondary issues; reducing the data moving to/from the Raid and the network bandwidth.

    Data Reduction:
    IMO, there's a BIG difference between 'critical business data' and the %userprofile% for all users, which would be typically massive and 99% unnecessary.
    All users should create a folder %userprofile%\Critical_Data and place 'business data' only therein. The backup system then targets ONLY that folder and its contents for capture.

    Bandwidth:
    If your RAID is to hang off the Network (ie the router) the for heavens sake get a Gigbit router, and make sure the NAS has Gibit too.
    Personally, I would look to restrict all LAN slots to 100mb and only let the NAS run full capacity.
    Joe User doesn't need 1000mb (even it he/she thinks so) as the industry has lived 3 decades w/o it.
    Using a Gitbit router with 100mb downlinks to systems will perform excellently and the activities of the NAS/Backup will not interfere.

    Remote Offsite Access:
    If you opt to run data live to a remote backup, get a second ISP connection/modem and a dedicated router for it.
    This allows realtime, prime shift transfers w/o impact to your business data.
    The sole resource contention on your entire system will reduce to the I/O activity of the data source(s).

    Company Systems:
    You haven't said what the business is, but business systems typically use things like:
    1. Exchange (ms email system)
    2. DNS
    3. DC
    4. Data Base
    Each of these entities (whether unique system or on a shared server) will need the Gigbit access too.
    The NAS/Backup system should capture these and be sure to get the configuration files for each.
    Notice, capture the Exchange system, not the user's email per se. This is a massive space/time savings.
  16. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    Got to run so perhaps Leeky could address concepts of a Logical Volume comprise of multiple physical volumes and the raid-1 covering the L.V.
    Multiple spares is a configuration issue and 'usually' supported: see the spec sheet for the vendor's offering.
  17. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    Sorry for the late response Cookiedude.

    Your limitation is purely available bandwidth, connections and physical space inside a case. If you want to run two hot spares that's absolutely fine, but it must be supported by the RAID controller to do so.

    Conversely, a RAID 6 array will tolerate two physical disk failures of the array without loss of data. This again, can be run with hot spares.

    That said, running with more than two hot spares in any one RAID 5/6 array in my personal opinion is pointless though, as it becomes cost inefficient to do so. If it was me, I would run the single hot spare and keep two (pre-tested!) replacement disks in a safe location for immediate replacement.

    Either way, it is essential you keep new disks for replacement of any potential disk failures. It would be a risk to rely on overnight shipping (or longer at weekends) in the event of a disk failure scenario.

    It depends on the software you use for the backup really. Most backup software includes the ability to verify backup images - Some do it automatically, but in either case you *must* ensure every backup, whether the original or incremental is checked for consistency.

    Another method is create an MD5 checksum of the filesystem at backup, and then mount the filesystem of the backup image and re-check the MD5 checksum. They should match on full backups. If they don't, it implies an issue.

    Always check, check and re-check. You can have a thousand backups, but if none of them are functional you might as well not have bothered.

    If you get a 5-bay NAS enclosure that supports multiple RAID volumes then you could run 2x RAID 1 arrays with a single hot spare covering both arrays. Again, RAID 5 is another option, as is RAID 6 and 10.

    The beauty of NAS solutions is the simplicity -- if they get too small, just add another NAS.

    You wouldn't need massive network bandwidth in order to perform backups. The first image would be large, but subsequent images will only be incremental backups that cover the difference in files since being last backed up. Your current connection could easily handle that if done daily, provided you were not restricted in total upload bandwidth by your ISP.

    The below point is essential:
    Make absolutely certain you adhere to this. You *must* use gigabit ethernet (also known as 1,000Mbps or 1Gbps) between all backup equipment to ensure the process is efficient and timely and doesn't effect the network bandwidth of those using 100Mbps connections.

    As per Jobeard's comments though... No one single user on the network *needs* any more than 100Mbps speeds in an office environment.

    Jobeard will no doubt have an opinion on how to achieve this, and I'd definitely check it out. My preferred method is this:

    Internet > Gigabit router > Gigabit Switch (server/NAS) > 100Mbps switches > 100Mbps connections (e.g. printers, computers other network infrastructure.

    On the gigabit switch would be the server, and your backup equipment. That way network traffic via the router (and the internet), the server, and the NAS would be at 1Gbps speeds with the enormous network bandwidth it offers, and the office equipment on the slower, 100Mbps side of the network. This will prevent network saturation slow down from too much traffic.

    If your workplace is more of a 9-5 than 24/7/365, it is entirely possible to get away with the one internet connection and take advantage of the night time to perform backups off-site by SFTP.

    Again, I have no commercial experience, so I'm drawing from self-taught knowledge of my own circumstances and my desire to learn new information. Make sure to verify this solution is adequate for your needs with others.

    Certainly, Jobeard.

    Logical Volume Managers (or LVM's as they're commonly called) is a software-based mass storage device manager that enables you to create large virtual volumes using multiple physical disks. It comes into its own with the ability to create huge server farms (thousands, hundreds of thousands) that enables you to add disks, replace disks, copy and share contents between every single disk allocated to the LVM.

    What this essentially grants you is the ability to create, remove and re-size Linux partitions whilst hot and on the fly. Another brilliant feature of a LVM is the ability to make snapshots of each LVM in its current state. You can also mirror multiple volumes creating an "RAID 1" like array. One of the biggest features however is the previously noted ability to resize partitions on the fly. Striping, otherwise known as RAID 0 is also possible.

    For example: /home is sat at 98% full, you need more space... you add another disk to the LVM and then dynamically increase the /home partition across that new disk -- this removes the need to migrate data from one disk to another, and creates a continuity between disks.

    You can then use LVM to create mirrored volumes, and even tell it how to behave in the event of a disk failure. By running with extra disks added to the LVM you can set it to automatically migrate to the additional free capacity of those disks in the event of one drive failing. Its a similar concept to that used by hardware RAID controllers, except this is on the software level.

    Another advantage of this solution is by creating a software-like volume management setup like this you remove yourself from the issues that RAID controller failures cause. It is not always guaranteed that the replacement of a faulty RAID controller will guarantee a stress free migration without any data loss. By implementing an LVM on the software level this issue is reduced to near zero.

    The LVM will be read by any OS that supports LVMs. So with Linux it would function perfectly on different hardware, or any other example of a hardware failure. The only real thing that trips up a LVM in my experience is disk-wide failures -- if all the disks simultaneously fail then the data will be lost.

    You also cannot use an LVM for the /boot partition, that must be on a partition or disk outside of the LVM.

    Out of curiosity what operating system are you planning on using with your new server?

    If you need further explanations of particular aspects of LVMs, or indeed other aspects of what I've said by all means ask away.

    EDIT: Wow, this is a long post! :haha:
  18. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    ps: Windows likes creating its own names for generic objects (eg generic(LDAP) is ms(Active Directory).

    Likewise, the generic(LVM) is ms(Dynamic Disks) :)
  19. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    We are a design agency and work on anything from graphic artwork, to 3D product visualisation right up to full interiors. Add in project management and we have quite a broad and diverse spread of data. We want to have all of this accessible from one location so no matter who has to work on a project they know exactly where to find the relevant files.
    The idea is that all business data will be centralised, all projects will be within the main company folder. The main problem we currently have is that all data is fragmented and every user has their own way of filing (and on their own machines) so if a designer is ill/on holiday we often waste a lot of time trying to find files. With the server we will have a unified folder structure so all project filing is consistent and this will make up the bulk of the data to be backed up. Any user specific data will be kept separate from this.
    I am fully aware of the merits of this, we already utilise a gigabit switch between the designers' PCs as we do quite a lot of network based rendering between machines. Would reducing this connection to the PCs have a negative impact on rendering performance or would we not notice the difference?

    Leeky - Thanks for the overview of LVM, certainly sounds interesting and may well be something to look at in the futre. However, I get the impression that such a setup would require a dedicated IT person/team/department, which is something I very much doubt we'll ever have! For now we'll just have to settle with the solution that I understand best :) I'm hoping we'll be getting a support service with the server but, again, will come down to cost!!
  20. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    Good for you! The suggestion re Critical_Data was targeted to those that allow business data all over the place on the users HD and then are forced into backups of 90% junk.

    With your RAID being used prime-time for active data, you certainly need a backup system.
    Perhaps I overlooked the issue but thought the RAID was a backup solution, not prime-time active data.
    Nothing wrong here, but your hotswapping will/should be done with much more care as the i/o rates on the raid
    will be much higher that when using it purely as a backup solution.
  21. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    re rendering

    Rendering per se is CPU intensive, not I/O. You should be able to benchmark i/o performance before, during and after a rendering to see this yourself.

    With centralized data directly on the RAID, you need something like this:
    Code:
    ISP ==Gateway ====== Server System
             |
             |====== NAS Device
             |
          100 mb
           switch
             |
            + Client PCs
    
    Using the NAS strictly as a backup solution, the active data would be
    centralized by accessing Shared/Mapped HD's on a Server system
    Code:
    ISP ==Gateway=== Server System === NAS
             |                ||
             |             Centralize
             |             Production
             |             Data Files
          100 mb
           switch
             |
            + Client PCs
  22. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    I tested this yesterday and realised the same. As long as we avoid 3D files in excess of 1GB (which is way bigger than anything I've currently done :)) I think the 100MB connection will be fine, thanks.

    This is close but would this prevent us from accessing the NAS over the network if the server crashes? Would this be a better solution?
    Code:
    ISP ==Gateway=== 1Gb Switch === Server System (with RAID 5 Storage)
             |            |                              ||
             |            |                       Centralize
             |           NAS                      Production
             |                                    Data Files
          100 mb
           switch
             |
            + Client PCs
    This way the NAS can be used as a backup when the server is running fine, but if it fails we can directly access the NAS over the network. Does this look correct?
  23. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    SWAP the NAS and Production Data File connections.

    Now in fact, the Production Data may be resident on a NAS and attached directly to the 100mb switch, but the backup Raid should be independent and should not be accessible to Joe User and have far less I/O traffic, thus enabling your hotswap and rotation techniques :)
  24. cookiedude

    cookiedude TS Booster Topic Starter Posts: 230

    I think you may have misunderstood me, both the Server and the NAS will have RAID arrays built in. Eg, server = 6 x 1TB HDD in RAID 5 (3TB usable) and the NAS = 5 x 3TB HDD in RAID 1. So the "hotswapping" would only occur on the NAS (which would be solely for backup duties), the only time we would take a drive out of the server (where our working files will be kept) is if a drive fails.

    It may be that I just had the diagram wrong. When I say server I'm working on the principle that the server and "centralised production data files" are one-and-the-same thing (though in reality I guess these would be 2 sets of hardware connected together?). Surely if I then have the NAS connected directly to this (as opposed to the switch) and the server fails, how would I access the NAS over the network?
  25. jobeard

    jobeard TS Ambassador Posts: 13,410   +314

    yes, understood and that's correct

    that's fine too but - -
    the implementation is what? just another RAID or is it a real system with inboard HDs?

    The layout suggested isolates the production data files from the backup(NAS).
    Having the NAS isolated frees bandwidth to the production data files and allows unfettered backups and anytime and facilitates offsite copies from there.

    (move the NAS wire to the switch :) )
    You don't have a failsafe environment in the first place. You have the right concerns but pick at only one of many comonents that 'could fail'.
    For failsafe operations, every component would need to be duplicate in the path from the user to every critical resource. This gets very expensive and in most cases is an over kill.
    The list would look like this:
    • two separate IPS connections
    • two gateway routers (1/isp connection)
    • one 1-gig switch for each router
    • two server systems
    • a common RAID share to both servers
    • the NAS connected to the primary switch
    • and even duplicated wiring from the ISP gateways thru to the
      switches to which the clients connect. Interconnecting the switches then
      allows fail-over to the alternate ISP connection
    There are 1,000's websites that don't have this level of reliability! This level is usually found only at BANKS and systems of that sort.

    btw: software failures on the server would be handled by your backup plan
    and only major hardware 'melt-down' would be a true exposure - - on the level of a
    fire/flood. Then you have several other issues that need solving before that server becomes an issue.


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