• StorageZilla (EMC):  “One has to ask is it really putting your money where your mouth is if you’ve been sure to rig the game so you can’t lose? 50% reduction with de-dup for low change rate heavily redundant data? Hell, you’re not even supposed to pick up the phone unless you’re running over 80% capacity and if you hit that number with one of the specifically defined data sets they support it means you probably don’t have de-dup switched on or have a pile of pre de-duplication snapshots stinking the place up somewhere.”
• The SAN Technologist (Independent blog, but employed by Dell/Equilogic):  This post is pretty fair about the entire issue, but compares it to Harley Davidson stating that motorcycles reduce tire needs by 50%.  “I just thought it was funny that the baseline for storage chosen wasn’t another RAID6 based configuration, but comparison to a RAID10 deployment.”
• Chuck Hollis (EMC):  Too much to quote effectively, but the standard response of RAID-10 vs. RAID-DP, along with a lot of the other caveats that the guarantee includes.  This is probably the most thorough vendor response that I’ve read.
• Robin Harris (Independent Analyst):  Robin didn’t discuss the guarantee, other than use it as a jumping-off point for primary storage de-dup.  “If the feature is free, de-duping some primary storage will be standard practice in most data centers within 5 years. As the de-dup technology improves and Moore’s Law drives performance, more and more unstructured data will be de-dup’d as a matter of course.”
• Scott Lowe (Independent Storage Professional):  On the Storage Monkey’s blog (Full Disclosure - I’m a member of the forum site), Scott asks for opinions but doesn’t share his (other than the common RAID-DP vs RAID 10).  “I’ll keep my thoughts to myself, except to say I disagree with the requirement that the baseline system (against which the customer’s system will be measured to determine if the 50% reduction is being met; more requirements here under “How it works”) use RAID 10.”
• Craig Simpson (HP):  “Of course some simple math shows that RAID 5 or 6 would save around 40% (43% for the case they chose) over RAID 1 on anybody’s array. So with all the other tools and restrictions their guarantee only saves another 7% over vanilla RAID 1.  Did they really think people wouldn’t do the math?”
• Jon Toigo surprisingly stayed out of the entire discussion.

After reading through the sheer amount of commentary surrounding this announcement, including NetApp’s own blog post in it, I think that this entire marketing “stunt” was brilliant.  First off, similar to IBM’s stealth launch of several storage products in the past month, this received a lot more commentary than most storage announcements.  From a “getting the product and message out there” perspective, NetApp received a lot of publicity for a fairly low amount of work.  At the very least, for any storage RFP in a VMware environment, competitors will have to answer why they feel the guarantee isn’t valid, and why they don’t have a similar guarantee.  After all, if it means “nothing,” then why don’t other vendors offer it?

After reading through the requirements, I believe that this is primarily for getting into the datacenter of new customers.  First off, the requirement for Professional Services isn’t too significant, since any new technology purchase typically comes with a PS engagement.  Secondly, from the NetApp blog posting about this offer:  “Once customers see the other advantages we have, in terms of performance efficient snapshots, rapid and efficient cloning and provisioning techniques, rapid data backup and recovery, and un-compromised data protection, they will realize a whole new way to manage their storage in a VMware environment.  Come for the space savings, and stay for the simplicity, efficiency and ease of use. Wouldn’t you like to try it?”

All guarantees have fine print.  I’m not exactly sure how any storage vendor would make a guarantee without similar requirements (Professional Services engagement, follow the best practices).  That doesn’t mean that the results are not achievable without PS… just that the guarantee requires them for it to be valid.  Let’s go to Craig’s quote above:  “So with all the other tools and restrictions their guarantee only saves another 7% over vanilla RAID 1.”  First off, I assume he meant to put RAID 5 there, and not RAID 1.   Only 7%.  On one hand… it is a 7% guarantee that no one else has.  On the other hand, 50% is the MINIMUM that is guaranteed.  I would love to see statistics in 6 months as to how much over that most customers achieve.

John Martin (NetApp) comments over at the SAN Technologist blog about the math behind it, and shows that without taking parity into account, a 41% reduction is likely.  Of course, 41% isn’t as sexy of a marketing term as 50%.

In the end, though, what this really comes down to is how much does a given vendor’s solution cost to achieve a given result… all of the guarantees really don’t mean anything if 50% of NetApp storage is equivelant (or more) TCO-wise compared to <insert random storage vendor here>’s storage.  Which is why I have to laugh at this tempest in a teapot… not one person mentioned the cost for a given deployment and compared it to the NetApp deduped deployment.  Because, quite honestly, customers really shouldn’t care about what technologies are used to achieve something, just that it is achieved as cost effectively and maintainable as possible.

Which is also why I thought the squawking about XIV using only mirrored storage was misplaced… but that’s one for another day.

• IBM’s XIV - Release 1:  The current release architecture of XIV its components.
• XIV - Storage Presentation:  Current software and storage presentation to hosts.
• XIV - The Coming Release 2:  Thoughts on what the next release of XIV will include.  I can’t believe this wouldn’t include concurrent code loads.

That didn’t work either… for some reason, the enter key refused to work after a ssh session was established through emacs shell mode… though normal SSH connections worked fine.  I still haven’t resolved that (and I’m not sure I’ll even bother further), but the configuration I ended up with works much better than my previous setup (plain putty).  Since it was fairly tricky to get the system working end-to-end, I figured I’d type it up in case other people were having similar issues.  The final result works as good as plain Putty for general SSH functions (except for a wrapping issue), allows for the use of SMIT menus in AIX, and looks much better than the default Cygwin shell.  The main issue that I continue to have has to do with long command lines… quite simply, the command starts "wrapping" onto itself and becomes a pain to modify. 

First of all, download the Cygwin installer and install any desired components.  I made sure to install the current version of emacs, emacs-el, ssh, and ncurses.  If you want to be able to use ‘clear’ from bash, ncurses is required.  I installed cygwin to c:\utils\cygwin.

Secondly, I modified the /etc/profile to move my home directory away from the system default.  To do this, add:

HOME=”/home/techmute”
export HOME

to the line in /etc/profile right before the line “# Here is how HOME is set, in order of priority, when starting from Windows”.

By changing the default home directory, it allows me to more easily transfer configurations from work to home where the usernames and profile locations don’t match.  After making that change, close out of Cygwin and relaunch it to seed the home directory with the default configuration files.

At the end of the .bashrc file, add the following text:

case $TERM in
    xterm)
    PS1=
    PS2=”> “
    PS4=”+”
    PROMPT_COMMAND=’
pcpwd=${PWD/$HOME/\~}
  [[ "${#pcpwd}" -gt 25 ]] && pcpwd=”..${pcpwd: -25}”
  echo -ne “\033]0;${USER}@${HOSTNAME} ${PWD/$HOME/~}\007″
  green=”\033[32m”; orange=”\033[33m”; cyan=”\033[36m”; off=”\033[m”;
  PS1=”$green\u$orange@$green\h $cyan${pcpwd}$orange \$ $off”
        ‘
    ;;
    dumb)
    PS1=”\u@\h \w \$ “
    PS2=”> “
    PS4=”+”
    PROMPT_COMMAND=
    ;;
esac

This configures the command prompt to look differently based off of whether it is a native bash shell or a bash shell spawned from emacs.  It prevents “ascii garbage” from showing up when you spawn a shell from emacs.  PLEASE NOTE:  I’m using the hacked version of putty as my terminal for this, so if you’re using the “default” Cygwin shortcut, it won’t work quite right.  Also, I borrowed this from somewhere online… if anyone knows the proper attribution, let me know.

Ngai Kim Hoong has an excellent site on configuring emacs for use with Cygwin.  Follow this link and add the portions you’re interested in to your .emacs file.  I would definitely include the shell configuration to launch bash instead of sh from emacs.

After this, the majority of the Cygwin configuration is complete.  The final steps replace the default Cygwin shell with something that doesn’t suck.  First of all, go to Google Code and download puttycyg.  This will allow you to run a modified version of putty as a cygwin terminal.  Secondly, go to this site and download the igvita desert theme.  It is packaged as a registry file containing putty customizations.  You’ll likely want to customize it further to suit your needs (I had to modify the columns and rows).

The end result doesn’t looks a ton better than the default Cygwin, but the wrapping issues still bother me daily when using piped commands.

mjd@techmute mjd $ lspv
hdisk0          00007690a14d9fee                    rootvg
hdisk4          00007690a14cae39                    None
hdisk5          0000769091324b51                    rootvg

There is a FS on testlv that resides in rootvg but has active storage on both hdisk0 and hdisk5. To consolidate and move that filesystem to hdisk4, its as simple as 3 commands:

extendvg rootvg hdisk4
migratepv -l testlv hdisk5 hdisk4

At this point, half of the testlv is on hdisk4, and half is on hdisk0:

mjd@techmute mjd $ lspv -l hdisk4
hdisk4:
LV NAME               LPs   PPs   DISTRIBUTION          MOUNT POINT
testlv                100   100   00..67..33..00..00    /test

mjd@techmute mjd id13982 $ lspv -l hdisk0
hdisk0:
LV NAME               LPs   PPs   DISTRIBUTION          MOUNT POINT
[...]
testlv                100   100   39..61..00..00..00    /test
[...]

To finish the consolidation/move, migrate the last half.

mjd@techmute mjd $ migratepv -l testlv hdisk0 hdisk4

mjd@techmute mjd id13982 $ lspv -l hdisk4
hdisk4:
LV NAME               LPs   PPs   DISTRIBUTION          MOUNT POINT
testlv                200   200   66..67..67..00..00    /test

This is easier than trying to use cplv or restoring a backup onto the new disk.

Another question would be are there any other portions of IBM that have a different definition for NDUs as well.

"Thus, as a node goes write-through and is upgraded after it flushes any dirty data in its cache, your performance should not degrade and we don’t ask that your stop applications or reduce workload during this time." (Emphasis mine)

I had always assumed that each SVC cluster mirrored the write-cache among paired nodes, but distributed the read-cache evenly… if there isn’t any performance degradation, then I must be mistaken.  I have a few redbooks on SVC I need to go over, maybe I can find something there.

Towards the end, Barry insinuates that SVC clusters can be replaced with upgraded hardware non-disruptively over a weekend… it’d be interesting to see exactly how large of an environment could be done.  I assume that you’d want to pre-stage a ton of zoning and masking changes.

"With the latest 4.3.0 release of SVC software that supports Vdisk Mirroring, even if you have to take a controller completely offline for some disruptive maintenance, SVC allows you to use the Vdsisk Mirroring feature to prepare for this event, offline the controller, fix it, and then only sync back the data that has changed since it went offline. I know of no other product that provides such a dynamic, non-disruptive and time-saving set of solutions to solve problems you or your storage administrators faces on a daily basis."

Wow, one of my favorite features of AIX LVM brought into a storage appliance… very cool, and I’m sure it is a great value to clients that don’t have enterprise storage arrays.

At the beginning of the post, though, Barry takes a jab at EMC’s Burke for ignoring his "loaded questions" about performance yardsticks.  Honestly, Barry admitted his questions were loaded… what did he expect, especially since the quoted specs were internal to the array?  I’m actually surprised that he pointed out Burke’s article, since it highlights that an IBM storage platform doesn’t have the ability to take a non-disruptive upgrade.

Unless, of course, it is behind an SVC…

Hmmmmmm…