the easiest way is to get with your emc account manager or sales ce and have them run your config through the tools they have available to them internally. that is what we had to do when we purchased ours. unfortunetly its not availabl,e to us customers.
@thomas, @rainer: The problem with asking the account manager is that it means every time I want to add a new LUN, I will need to ask them upfront how much space the new LUN will use within a specific pool. This is really not practical or realistic. Why do we need special tools to determine how much space a new LUN will take up? Is the LUN allocation so hard to determine? This seems rather basic functionality that should be available to anyone.
i understand your point, we were able to do that b/c we were still in pre-sales, if you are trying to do this on the fly with a box already owned, i can see the hassle in having to go back and forth. i tried to figure out the numbers on my storage pool but that were not coming out exact, that were almost a gb higher then what was showing up in unisphere, the other other thing that i noticed was the % of usable storage on our 600 and 2000 drives were different the 600 was at 89% and the 2000 was at 91, i would figure that would be the same. if you wanted a close estimate that you should be able to put all the data into excel that would give you a pretty accurate estimate, on 15TB pool that i have i was 1GB off . i'll take that.
@thomas: In our team, we created an Excel document as well but it would be good to have an accurate method to calculate available capacity. Given that EMC is a storage company, for them not to be able to tell customers how much space is used by a LUN, without the use of internal, non-customer facing tools, seems quite bizarre.
The sad part is that in the past, with the older models, the simplicity allowed us to better understand how storage was allocated and how the LUNs should be laid out. With the move towards virtualisation, the complexity seems to have increased without ensuring that information customers had in the past were still easily available.
@rainer: Do partners have access to more information or just access to these internal tools? In the past, we have worked with out EMC sales team to size new arrays and the information they provided was quite rough even using the internal tools. Is there a reason why the sizing information is not easily available?
Partners can get hold of the same tools that the EMC presales teams uses, and also a lot of the diagnostic tools EMC uses, this depends on the Partner level that you have achieved..
To get full access to all the tools the Partner would have to get into the Uspeed performance group
The uspeed members has tools that can calculate what youre asking for.
Can I ask you why this is an Issue at all.
When I look at the problem raised i see two things.
1. At most we are talking 2-5 Gb space that may be calculated wrong ,But this is in an age where the arrays we use has the capabillities to scale to Peta Bytes, and in pools that has Tera bytes or hundreds for tera byte of space.
So at most we are talking about 1/1000 of the total capacity maybe even down to 1/ 10000000.
2. If your array really need that close calculations you are in serious need of extra capacity.
I have never run into anyone who had the requiremens to calculate this down to the last bit, byte ot block.
and I think that this may be tha answer to why the tools to do this is not general available...
@jim: Thanks for your reply. Let me use the following example to show why I feel this is an issue. My sales team comes and tells me that a customer is urgently asking for 1 TB of space. I have 1028 GB available. If I need more, I will need to order additional drives which could easily take up to three weeks. What should my response be? If I say, I have the space, we can quickly close the sales deal and win this business. If not, then I will have to ask the sales team to delay the customer request for up to three weeks and risk the chance that the customer will go elsewhere.
Without knowing whether or not I have the space becomes critical in this situation. You may raise the point that I should probably have more than 1028 GB available. But I could have 10 TB of space available and get an urgent request for 10 TB of space. While most customers may not care about how many bits are available, it does matter when attempting to create a LUN in response to a critical business need.
So what this comes down to is giving the customer more information about their environment rather than less. EMC has moved towards giving customers more control over using and managing CLARiiON and VNX arrays with tools like USM. However, not having what I consider basic functionality of any storage array, namely the precise amount of space available and how much space a LUN will take up is making it hard to manage these arrays.
I can understand that EMC might have advanced performance analysis tools that are not readily shared with customers because of the background knowledge needed to understand the metrics and what they really mean. But capacity should not be something that requires intimate knowledge of the VNX or CLARiiON architecture.
the .02 could change depending on your write pattern on your application and the number is an approimate , i noticed it to be a little off then what was actually used and found the number to be closer to 026
Rainer_EMC
4 Operator
•
8.6K Posts
0
March 22nd, 2012 01:00
Are you a customer or a partner?
g.srinivasan
29 Posts
0
March 22nd, 2012 07:00
Customer.
Rainer_EMC
4 Operator
•
8.6K Posts
0
March 22nd, 2012 13:00
Yes - that's what I suggest
thomashmaine
49 Posts
0
March 22nd, 2012 13:00
the easiest way is to get with your emc account manager or sales ce and have them run your config through the tools they have available to them internally. that is what we had to do when we purchased ours. unfortunetly its not availabl,e to us customers.
g.srinivasan
29 Posts
0
March 22nd, 2012 14:00
@thomas, @rainer: The problem with asking the account manager is that it means every time I want to add a new LUN, I will need to ask them upfront how much space the new LUN will use within a specific pool. This is really not practical or realistic. Why do we need special tools to determine how much space a new LUN will take up? Is the LUN allocation so hard to determine? This seems rather basic functionality that should be available to anyone.
thomashmaine
49 Posts
0
March 22nd, 2012 19:00
i understand your point, we were able to do that b/c we were still in pre-sales, if you are trying to do this on the fly with a box already owned, i can see the hassle in having to go back and forth. i tried to figure out the numbers on my storage pool but that were not coming out exact, that were almost a gb higher then what was showing up in unisphere, the other other thing that i noticed was the % of usable storage on our 600 and 2000 drives were different the 600 was at 89% and the 2000 was at 91, i would figure that would be the same. if you wanted a close estimate that you should be able to put all the data into excel that would give you a pretty accurate estimate, on 15TB pool that i have i was 1GB off
. i'll take that.
g.srinivasan
29 Posts
0
March 23rd, 2012 11:00
@thomas: In our team, we created an Excel document as well but it would be good to have an accurate method to calculate available capacity. Given that EMC is a storage company, for them not to be able to tell customers how much space is used by a LUN, without the use of internal, non-customer facing tools, seems quite bizarre.
The sad part is that in the past, with the older models, the simplicity allowed us to better understand how storage was allocated and how the LUNs should be laid out. With the move towards virtualisation, the complexity seems to have increased without ensuring that information customers had in the past were still easily available.
@rainer: Do partners have access to more information or just access to these internal tools? In the past, we have worked with out EMC sales team to size new arrays and the information they provided was quite rough even using the internal tools. Is there a reason why the sizing information is not easily available?
Jim_Hegner
212 Posts
0
March 23rd, 2012 13:00
Partners can get hold of the same tools that the EMC presales teams uses, and also a lot of the diagnostic tools EMC uses, this depends on the Partner level that you have achieved..
To get full access to all the tools the Partner would have to get into the Uspeed performance group
The uspeed members has tools that can calculate what youre asking for.
Can I ask you why this is an Issue at all.
When I look at the problem raised i see two things.
1. At most we are talking 2-5 Gb space that may be calculated wrong ,But this is in an age where the arrays we use has the capabillities to scale to Peta Bytes, and in pools that has Tera bytes or hundreds for tera byte of space.
So at most we are talking about 1/1000 of the total capacity maybe even down to 1/ 10000000.
2. If your array really need that close calculations you are in serious need of extra capacity.
I have never run into anyone who had the requiremens to calculate this down to the last bit, byte ot block.
and I think that this may be tha answer to why the tools to do this is not general available...
Most people would not use them anyways...
g.srinivasan
29 Posts
0
March 23rd, 2012 14:00
@jim: Thanks for your reply. Let me use the following example to show why I feel this is an issue. My sales team comes and tells me that a customer is urgently asking for 1 TB of space. I have 1028 GB available. If I need more, I will need to order additional drives which could easily take up to three weeks. What should my response be? If I say, I have the space, we can quickly close the sales deal and win this business. If not, then I will have to ask the sales team to delay the customer request for up to three weeks and risk the chance that the customer will go elsewhere.
Without knowing whether or not I have the space becomes critical in this situation. You may raise the point that I should probably have more than 1028 GB available. But I could have 10 TB of space available and get an urgent request for 10 TB of space. While most customers may not care about how many bits are available, it does matter when attempting to create a LUN in response to a critical business need.
So what this comes down to is giving the customer more information about their environment rather than less. EMC has moved towards giving customers more control over using and managing CLARiiON and VNX arrays with tools like USM. However, not having what I consider basic functionality of any storage array, namely the precise amount of space available and how much space a LUN will take up is making it hard to manage these arrays.
I can understand that EMC might have advanced performance analysis tools that are not readily shared with customers because of the background knowledge needed to understand the metrics and what they really mean. But capacity should not be something that requires intimate knowledge of the VNX or CLARiiON architecture.
thomashmaine
49 Posts
0
April 4th, 2012 07:00
Vayuhanuman,
i found this when looking at some emc documentation today. it may help you in trying to figure out your lun sizes
page 17
metadata overhead(inGB) = LUN Size (in GB units) * .02 + 3 GB
the .02 could change depending on your write pattern on your application and the number is an approimate , i noticed it to be a little off then what was actually used and found the number to be closer to 026
http://www.emc.com/collateral/hardware/white-papers/h8222-vnx-virtual-provisioning-wp.pdf