Promise VessRAID 1840i

I just installed two Promise VessRAID 1840i units for a client, each one loaded with 8 x 1TB Seagate Enterprise drives. With 8 more drive bays, we can easily take each unit to 24TB without replacing drives, and you can add up to 3 more expansion enclosures, 16 bays each, for a maximum total of 128TB. Impressive, to say the least.

My major issue with purchasing these units is that there is no good review information online for any of the Promise gear. No user forums, either. So you don’t know what you’re getting in to, and have to trust the word of the sales guy (did I mention these things are generally only available through reseller channels?). To perhaps help the next guy, I wanted to provide some feedback on my experiences.

Load

I got my units empty, which I hear they won’t be doing anymore. Came with all the necessary trays and screws to load drives. SATA drives work with no adapters (unlike some Dell arrays), haven’t tried SAS drives. Simple as pie. Biggest trouble was dealing with all the trash: boxes, bubble wrap, and clamshells for the hard drives from CDW.

Power Up

The dual power supplies are rated at 450W each, 900W total, and a max draw of 9A on 100V. So I was worried about overloading my 15A circuit with two of these starting up. From experience, however, the half-loaded unit draws far less. A CyberPower UPS (very nice unit, by the way) shows a peak wattage at startup of 225W, which is only 2A at 110V. Wattage once the fans have gone to normal speed is under 150W. (This is one expensive light bulb!)

UPS Compatibility

The VessRAID has two USB ports on the back to connect the unit to an Uninterruptible Power Supply. (The second one is for an un-defined support mechanism to upload config or debug files via flash drive.) Given that there’s a pretty well-developed UPS standard for using USB HID interfaces, and I figured just about anything new should work. Nope.

The hardware compatibility list provided by Promise lists only two compatible units: APC Smart-UPS 1500, and APC Smart-UPS 3000. My guess is they’re using an antiquated APC protocol. Important note: you cannot use the cheaper SC line from APC, because they only include a serial port, not a USB port, which you get at double the price on the non-SC units. So you probably don’t want to stray from the hardware compatibility list, particularly when buying a UPS.

If, however, you’re creative, you can make something work. If you have a regular server attached to any other UPS, you could use SSH or telnet scripting to login to the VessRAID CLI and initiate a shutdown. I tested it using the Telnet Scripting Tool by Albert Yale (widely available, including at an unauthorized archive of the guy’s software).

Initial Configuration

Initial config, particularly for the network settings, is best done via the serial console port. The units include a RJ-11 to DB-9 cable, but you’ll need a working serial port on your PC or laptop. Given that most laptops don’t have one these days, you might want to invest in a USB to Serial adapter. The Trendnet TU-S9 was cheap and seems to work well.

Management through the web interface must be done on the management port, so configure it in a subnet that you can access from your other machines. NAS and iSCSI will happen through the iSCSI ports. NAS should be on the same network as the clients; you might want to isolate iSCSI traffic in a different subnet (or even a separate physical network).

Configuration (NAS)

All the “i” units of the VessRAID 1000 series (i.e., the 1840i) are mainly intended to be used as iSCSI devices, and have 4 x Gigabit ports for that very purpose. However, they also have a built in Network Attached Storage system that can be used to provide Windows sharing, FTP, and NFS access.

The pros of this arrangement:

  • The VessRAID units operate as their own distinct servers, and need not rely on any other machine to do their storage work. Particularly useful on a smaller network, or for a very particular storage task.
  • The units will sync themselves automatically, using a customized version of rsync. You can easily configure this backup from one unit to another in the web configuration software.
  • Multiple clients can access the same file system at the same time. Remember that with iSCSI, the array is presenting the low-level data blocks to the initiator on the client (a Windows server, for instance), so there is no way that multiple clients could use one file system at the same time — unless you share it through the client.

The cons of this arrangement:

  • Active Directory support (available via a firmware upgrade) is poorly implemented. Getting the NAS connected to your domain is a touchy matter, requiring an exact combination of case-sensitive domain and user names that I got to work, but couldn’t figure out.
  • Active Directory permissions are even worse. Instead of specifying which users or groups should be used in the ACL for a particular share, the NAS web configuration presents ALL of your users and groups, with default full access permissions.  If you want to include only a few users, you have to click “Deny” on every other users. If you want to include a group, you can’t effectively, because the Deny permissions on individual users will override Allow permissions on a group. This implementation is absolutely useless.
  • Poor support for Windows permission lists. This is true in any SAMBA implementation, because the underlying Linux-based file system only supports the user/group/all permission scheme. So the NAS can’t handle fine-grained permissions on folders or files within a share.
  • Speed. Access through iSCSI is much faster.

Configuration (iSCSI)

I originally configured the units in NAS mode, but the client wanted to put some Windows user shares on the array, which require fine-grained folder permissions. So I reconfigured the logical disk for iSCSI use.

The simplest approach is to use Microsoft’s iSCSI Initiator (included in Windows 2008 server, and available to download for Windows 2003 server). There are good instructions available in the VessRAID documentation and from Microsoft on how to get this to work. Especially helpful for best practices is Microsoft’s step-by-step guide.

After connecting the client to the logical disk using iSCSI, you format it in the Windows Disk Management utility. To enable use of partitions larger than 2 TB, you have to convert the disk to use GUID Partition Tables (GPT). Once done, the whole space should be available to format using NTFS. I won’t discuss it here, but make sure to consider the types of files being stored, and other requirements (such as Shadow Copies or NTFS Compression), when choosing an appropriate cluster size.

Benchmarking

I used PassMark’s Performance Test software to obtain some basic benchmark numbers for the VessRAID’s performance. This is using a standard Broadcom Gigabit interface on a Dell Poweredge 1900. All arrays are RAID5.

Local Array
3 x 160GB
Dell PERC 5/i
Sequential Read 61.8 MBps
Sequential Write 92.5 MBps
Random R/W 7.2 MBps
WriteThru WriteBack
VessRAID 1840i
8 x 1TB
Gigabit iSCSI
Sequential Read 105.8 MBps 105.8 MBps
Sequential Write 27.9 MBps 90.6 MBps
Random R/W 12.4 MBps 31.9 MBps
ReadyNAS NV+
4 x 500GB
SMB/Gigabit
Sequential Read 12.0 MBps
Sequential Write 4.5 MBps
Random R/W 5.9 MBps

Note the very significant performance difference between the WriteBack cache setting the WriteThru cache setting on the VessRAID. WriteThru writes the data directly to the disks when it arrives. WriteBack holds data in cache before flushing it to disk, which is far more efficient, as sectors can be written together and larger chunks at a time. To safely do this, however, requires a battery backup for the cache, so that if power is cut suddenly you don’t lose that data (which hasn’t yet been written to disk). The problem is that Promise does NOT include the battery with the units. It’ll cost you an extra $100. You’d figure on larger units like this they wouldn’t nickel-and-dime you, but they do.

Correction: I had reversed the WriteThru and WriteBack terms. I have corrected it in the text above, after the feedback from the commenter below.

Posted in Product Reviews and tagged , , , , .

20 Comments

  1. Thanks for this post. I’m considering purchasing two of these units. There not too much info on the internet about VessRAID units. How long it took to build RAID array? I’m planning to populate all 16 bays with 2TB disks.

  2. Just purchased two 1820is which run the basic stuff and already finding interesting.
    Apart from the usual niggles of ALL domain users being allowed to read write to any NAS Folder, am finding it a good value for money.
    For users who read this post *before* buying their units it would be advisable to check with Promise on the supported drives. They tend to get picky on support if you are not using a ‘enterprise’ class drive.

    Likes:::
    – Dual hot pluggable power supply
    – spare port for management traffic
    – No fancy extra features : NAS (CIFS/NFS) and iSCSI
    – Robust web interface (till now)
    – Reasonable value for money

    DIslikes ::
    – Poor documentation of getting from A to B (all bits are there , you need to piece them together)
    – Poor NAS security implementation : all domain users are given read write access by default.
    – NAS implementation is not straightforward – am still struggling to get this working

    Would say that contrary to my expectations, the iSCSI setup was easier to get up and running than the NAS bit.

    Since we are implementing a vmware setup and these are early days, things could change – and fast.

  3. Hey there and good day!

    Thanks for the post. Just as a note, I think you reversed WriteBack and WriteThru in describing their impact.

  4. Thanks for the details. I’ve used the Mtrak series before, and have been searching for a while to find some useful information on the VessRAID.

    Are you still happy with the devices?

    • I am still very happy with the devices. Performance is excellent, particularly after installing a dedicated NIC on the server with an on-board iSCSI offload engine. That relieves the processing pressure on the server.

  5. Value for Money !!

    Very easy to setup,quick & reliable.

    I have been using this for 6 months in a SMB environment. Also their Phone Support is better than most of the big storage Vendors i have used before.

  6. I am looking at purchasing one but that comes with 8 drives populated and I want to immediately upgrade to the 16 drives, do you recommend a particular hard drive? Do you recommend the seagate constellation raid hard drive or have you had success with a different hard drive?

    • Be very careful to get drives on the hardware compatibility list for this system. The Seagate Constellation ES drives provided the best cost-per-TB (among the approved drives) when we bought them.

  7. We run lots of VTrak m610i and VessRAID 1840i since a couple of years back, and overall we’re happy with them. They’re fairly cheap and perform pretty well. Also, we never lost a unit. The only issue we have that there seems to be a memory leak in the administrative software, which makes the GUI/CLI unavailable, but the device is still processing iSCSI traffic. So, all in all, a good price/performance deal. It is still cheaper to build a storage system yourself, for instance, using solaris on supermicro chassis, but promise is far easier to manage than a full-blown solaris box.

  8. Thanks for the VessRAID review. I have a couple of them in my network and they are also working well. The only thing that makes me a bit nervous is the single RAID controller. From a fault-tolerance point of view, the controller is a single point of failure. For future network storage, I am considering moving up to the E-series VTrak product because it seems a bit more robust overall and does have dual RAID controllers. Do you have any experience with these?

  9. Thanks for a good overview. I’ve been extremely happy with the Vtrak M300i and needed to buy a couple more units. I’d settled on the VessRAID 1840i but wanted to see a review or two before clicking the submit button on an order.

    Google brought me here, and so far it’s confirmed what I’ve always believed about our Promise arrays– good price, great hardware. My only complaint with VessRAID is they wll only replicate with other devices on the same subnet. (confirmed by Promise support)

    The sales guys tried to up-sell us on the Enterprise products, at 5x the price. We said No Thanks and built a transparent layer 2 bridge between our two main facilities so these units could talk with each other. IMO, any device that already communicates via TCP/IP should NOT be crippled to a single subnet. That made me grumble.

    The other nit to pick, is Promise forces us to buy 8x SATA disks, which we do not want or use. As a service provider, we buy disks by the case at a LOT cheaper price– plus WE get to control the brand of the disk (we like Seagate Constellations and Cheetahs).

    One of the arrays we bought will be filled with 15k SAS Cheetahs– so we have 8 SATA disks laying on the shelf we don’t need. Total waste of money. Too bad Promise took our options away.

    • I got these units just before Promise required them to be purchased with drives, which is robbery, quite honestly. You add some good points to the review, thank you.

  10. Just purchased the 1840i. Having some real issues this this unit and active directory setup. I would agree with everthing in this article and the comments made by others. I also have a Vtrack which was easy to set up in a SAS configuration connected to multiple servers, but this thing is a bear to get set up in a NAS configuration. haven’t tried ISCSI yet on this box, but that wasn’t what I bought it for. Working with tech support on trying to get it resolved usingh the 3.06 firmware update but still they are having to send me up to the next level of support. Seriously considering putting it back in the box and sending it back if they don’t get this resolved soon.

  11. We have 4 VTrak M610i being used for streaming 14 channels of 12MB/sec video. Heavy use, works great. Occasional problems but this is about the VessRAID 1840i. We installed two of them and immediately began having problems. We immediately began having problems. We are currently working with technical support but let me warn you. Under demanding situations the VRAID does not perform well. Reads are slower than the VTrak and writes are horrible. Writes slow down the reads horribly. If tech support cannot help us these drives are useless.

    Stick with the M610i…

  12. Update. We ended up purchasing M610i units and they had performance problems also. Something has changed in the units which is not reflected by any version number. Please understand that our use is very demanding. The old VTrak M610i units work fine. New units and the VessRAID 1840i do not meet the demand. Technical support basically denied our claim that there was a problem.

    • You have to be very careful to buy drives on the compatibility list (available at the Promise website). But there indeed are a good number of 6Gb/s drives on that list. Not sure if the interface in the unit is truly 6Gb/s, but the drives are compatible.

  13. Greetings,

    can anyone post steps on setting up NAS on an 1830i? To note, I’ve created the file system, configured share folders and permissions on said folders. Joined domain (I had to use the chosen DCs IP address since its host name and FQDN did not work) and added to DNS. I can ping the 1830i by IP and hostname, but cannot browse to it using a UNC path. I think I am missing something critical that is preventing this from working. I read that it uses iSCSI for NAS, but the four iSCSI ports are used to connect it to the two VMware hosts (which works fine and how I originally had it set up). Another note is that I have 15k SAS drives still in iSCSI presented to the VMware hosts. I have four 2TB SATA drives I configured for NAS. The iSCSI ports are on two different subnets (neither of which are the LAN subnet) so I am not quite sure how iSCSI is used for NAS on these boxes. I entered a support ticket but did not hear back from support with a useful answer. I submitted the subsystem report but still nothing. Been about a week now.

    Thanks a lot for any help with this

Leave a Reply to Erik Oliveira Cancel reply

Your email address will not be published. Required fields are marked *