HA - Admission Control-number of failures of the host in the cluster can tolerate

Similar Questions

• How to get the 'description' of a control property if the control is a part of the cluster?

  Hi, dear all

  LV offers the possibility to work with the property 'description' of the individual control of the VI. The use of knots of property: reference VI > front propert > control [] property > Description.

  Unfortunately, I found a way to set or get the description of a control if it's a part of the cluster =)

  Could someone suggest the idea?

  Thanks in advance,

  Max

  interesting problem, I tried, take a look.

  your

  RZM

• Odd number of nodes in the Cluster controller NSX

  Why odd number of knots are required in the controller NSX Cluster?

  The election of the master for each role requires a vote by a majority of all active and inactive nodes in the cluster. This is the main reason why a Cluster controller must always be deployed based on an odd number of nodes.

  See Page 10-11 of this guide for more information: https://www.vmware.com/files/pdf/products/nsx/vmw-nsx-network-virtualization-design-guide.pdf

• What is failure of the cluster?

  I want to know the definition of Fail on the cluster and why we we there?

  It's normally a network configuration in which, if a single machine in the cluster (or set of computers) fails then another machine will resume the work of this computer failed on a hot standby basis (IE so that all work that has been processed by the machine failed is not lost).

  It ensures that work is not lost.

• Failure of the Cluster stretched VSAN scenarios

  I read of CHogan valuable document VSAN stretched Cluster I guess I need more help on the following issues

  Locally, the reading is 50% in the site where the computer virtual is deployed and 100% on the site of the replica?

  I have to install the witness on a geographical site or it will work on sites with different cluster?

  Thank you

  
  

  Town of reading is 100% on the very site where the virtual computer. In other words, the virtual machine is always reading in the same place and not cross the link between the sites.

  You need a 3rd site for the witness. You cannot place it in one of the other sites, because if this site does not, you have lost the majority of the components (replica 1 + 1 = 66% control), so that the virtual machine is no longer accessible.

• Admission control and wrap a reservation

  Dear guys,

  as long as I do not have a reservation to my res stocks (with limits) I find it really hard to check how many slots is used if I select "chess tolerate the host cluster" admission control.

  Normally slots are based on VM reserve, but what about reservation assigned to ResPools?

  Then I check the Runtime Info on my group and I do not clearly have some values:

  Subtotal in the cluster = > ok

  used slots = > ok

  places available = > what does mean?

  failover slots = > what does mean?

  For these 2 values, I went to vmware documentation, but it wasn't clear to me...

  Thanks in advance.

  Daniele

  I tested it slots is based on the vm not the Resource Pool reserve reservation

  Example: -.

  Number of slots total = 22

  Used machines slot = 4 (depending on the number of running virtual machine)

  Available places = 7

  Failover = 11 Slots (depends on how many hosts failure cluster can tolerate) if it is 1 and we have 2 node cluster, then this is 50% of the total number of connectors. Means, that you can use according to this example, you can feed only on VM 11 are now no more than that.

  If we don't do not tell me it please

• HA admission control, no reservation

  Hi all

  I read trying to get my head around how HA admission control works with virtual machines that have no defined reserves.

  My understanding is that the HA system assigns a default value of 256 Mhz CPU and 0MB + of memory overload VM who do not have reserved resources. This default value would be the size of the slot to determine the amount of the VM, the cluster can run.  The number of places is in turn affected by the number of host failures that can be tolerated or the percentage of resources as production capacity unused failover.

  Where I am confused, this is what happens when HA assigns (assuming that no reserve of VM) default slot size (256 Mhz + (0 MBoverheadMB) to a cluster when the VM memory usage is greater than 0 MBoverhead?)  I guess that there is a possibility that HA slot allocation could exceed by far the cluster resources real/usable in the event of failover/maintenance etc. mode

  For example -.

  A cluster using host to 32 GB with a bunch of 1vcpu 4 GB VM without reservations the value.  According to the guide of resources each VM would have an overhead of 165.98 MB, resulting in a fairly large number of slots for each host.  Assuming that the CPU resources are sufficient, a host might have something like 190 slot machines to play with.

  Does this mean that HA would allow 190 4 GB without reserve in the cluster VM before that admission control would still prevent or add power on VM?  If this is correct, it seems quite possible more than commit the very much, defeating the point of assignment of a host for failover or the percentage of resources etc. as each host in the cluster could be running over 100% of use of.

  Assuming that all virtual machines must stay without reservation, how could configure HA of follow-up admission control admissions (chess hosts or percentage) without saturating the remaining hosts?

  EDIT - this link summarizes my question a little more eloquently that I could put it, note the linked article is 2008 and the figures may be out of date.

  http://vinternals.com/2008/12/ha-slot-size-calculations-in-the-absence-of-resource-reservations/

  See you soon.

  link added

  As shown in the link you posted (and guide availability VMware page 26 - http://www.vmware.com/pdf/vsphere4/r41/vsp_41_availability.pdf) HA admission control uses to determine the size of the slot if no reserve is specified on the virtual machines, you can use HA advanced options to increase the default values: das.vmMemoryMinMB and das.vmCpuMinMHz. This will increase the size of the slot and reduce the number of places available in the cluster.

  Elisha

• HA matter of admission control

  It will probably seem like a silly question.  I'm trying to set the parameters on a HA Cluster in vSphere 5.5.  We have a minimal implementation of vSphere: a site, a single cluster, 3 guests.  We have now 5 virtual machines and would accommodate no more than 12 at any time, (I doubt that we will find ourselves with more than 9).

  We use the option of admission control to use a "percentage of unused reserved production capacity as cluster resources in failover.  I'm trying to define that it tolerates more than one host being down at one point, or in other words, there must be at least 2 of the 3 hosts running at all times.  I should probably select 'Failures that tolerates the home hub' and set it to 1.  But I read in a document on the subject (as the percentage option) was desirable for performance reasons.  But this is what confuses me.  To indicate to the cluster to tolerate up to a failure of the host, should I choose 66% or 33%?  That is the question.  I read a lot of literature, but I can't seem to find an answer to this simple question.  Below in the image, I have made an assumption and set it to 66%.  A single document I've read has explained that I would have guessed that it is 33%, but then I noticed that with all 3 hosts in normal operation, the ability to failover is 99%, and we want that it tolerates up to a failure of the host who would put at 66%.  So if I go by the percentage and want to allow the failure of a host to most, is this (66%) the correct setting?

  

  Thank you, very much!

  Sam L. flow

  Hi Sam,

  Welcome to the forums! With percentage based on admission control policy you choose how your cluster resources, you want to book for use in a failover, so for your scenario where you have 3 guests and want to tolerate 1 fault of the host you would set them to 34% (round).

  Keep in mind with this policy to control intake that counts against the % of cluster resources is: overload of virtual machine (CPU & Mem required by host/ESXi to run the virtual machine) + and a reservation for the virtual machine. This is because the admission control only guarantees that your VMs will restart, not that they will perform well.

  Hope that answers your question. If you are interested in reading more about HA I recommend:

  http://www.yellow-bricks.com/

  http://frankdenneman.nl/

  Amazon.com: VMware vSphere 5.1 Clustering Deepdive eBook: Duncan Epping, Frank Denneman: Kindle Store

  See you soon!

• How is admission control information is pass on host when vcenter is out of service?

  I expect a scenario when vcenter is down and in the meantime ESXi host is harnessed. How this admission control will be coming in this scenario? It will restart the virtual machines without taking into account the policy of admission control? or how? I don't know how information moves from vcenter for HA.

  Can anyone help me please with this. Thank you very much.

  Thanks much for the reply. Thus, admission control information will be with the guests? where this information is stored inside the host, we can see that or we can change it from the host?

• vSphere HA Admission Control Calculator

  Hello world

  Today, I tried to place a host in maintenance mode and received the infamous "insufficient resources to meet the level of failover configured for vSphere HA. I worked around this by temporarily disabling the control of Admission, but it got me wondering how the cluster would tolerate the loss of one of the hosts.

  This is what looks like my cluster:
  -2 x Dell PowerEdge R720s with 96 GB of memory and 2 x Intel Xeon CPUs E5-2650 (12 cores) per host
  -ESXi 5.0 Update 1 + the latest patches
  -vSphere active HA
  -Admission Control Enabled (set at 50% of the resources of the reserve)
  -Active DRS
  -16 VMs Windows with the configuration of the CPU from 1 to 4 vCPUs and 1 GB to 4 GB of memory.

  I have studied this to try to determine what the cause of the problem. To do this I have set up a calculator based on Excel to determine the capacity of cluster failover. Calculations are based page 22 of «vSphere availability - ESXi 5.0»

  My ad has two parts to it:

  (1) the calculator attached that I would be very grateful if someone would review and confirm that it is correct (I hope it is and others will find it useful). I protected the leaves 'CPU' and 'Memory' so they can be used as examples. Just edit the details of CPU/memory host in other sheets to match your environment. I've left the details of my cluster in there I thought that people might use it as an example. If you like I can clean up towards the top.

  (2) a question: how will my cluster behave with the loss of a single host? If the behavior of a host in maintenance mode is something to go by not all virtual machines will begin on the hosts of the survivors that the processor requirements cannot be met. However, I read that in an event of failover HA will ignore the policy of admission control and try to start the virtual machines on the host of the survivor. Someone can it confirm please?

  I hope this is clear enough. If this isn't the case, I'll be happy to provide any additional information.

  Thank you very much!

  Sean

  Post edited by: STK2. Spelling, grammar correction. Deleted Excel document (will provide doc updated in a separate answer).

  HA admission control uses the reserves of cpu and memory for the virtual machines, not the configured and memory, the computation of the failover capabilities. You use probably the latter in your calculations. Under the tab "Resources" of the pole in order to see the reservations on your virtual machines (by default, they are 0).

  Elisha

• How to access the property of ListBox inside the Cluster element names?

  In LabVIEW 2010, I have a group of controls on the front panel. In this group, I have a ListBox. How can I access the Item property for the ListBox object names in my block diagram.

  Of the bunch, I can get control ListBox, but which returns a value of I32, probably the index of the selected item.

  In the block diagram, how can I get the name property of the item in the ListBox control since a reference to the Cluster?

  Thank you.

  using the table 'orders' in your cluster, you can access each item. Next, you will need to convert the reference to a 'class more specific' with a reference to an arbitrary list box (or a constant reference of the required type), then you can access all the properties of your listbox.

  

• Insert into the cluster by string name

  Hello

  I am writing a Labview program to query .NET database management system and get the connected device (like USB CDC) listed with Port of corresponding Com, VID, PID, manufacturer of SN name ect...

  I got to the point where I get the channels I need and want to organize them in a cluster table.

  Here is my code, I wanted a better way to replace section circle of the code.

  Basically, I can get programmatically the cluster name, but when the cluster wads, I can't figure out a way to do it programmatically inside the while loop: a loop on the number of items in the cluster and by placing values in the right place.

  

  Is it possible to do?

  Thank you very much

  Amine

  Altenbach says:

  If the cluster contains exactly three elements of the chain (nothing else!) and they are classified as in the node of your 'bundle by name", all you have to do is on the"table of cluster"output size 3 and it wire in a table build node (upper entrance wired to your array of cluster and botton imput cable to the new cluster) Wired output by the right side of the image).

  Here is a simplified illustration which simply sets the value of the label. (top image). Because the labels are defined at compile time, all you need is perhaps to get the names of once at the beginning of the program, and then use a range of simple string instead.

  Another possibility would be to use the reference to the element to set the value inside the loop, and then get the final cluster value later (at the bottom of the image).

  (There are some simplified examples. All you need is to replace the code that gets your new string instead.)

  

• Help with the cluster in table for the cluster size difference, please!

  I will admit to still hurt with the berries of LabVIEW, and as usual, the behavior in the vi attached is meaningless to me!  The attached vi shows a cluster 6 element being converted into a table, then immediately to a cluster.  The reconstructed cluster has 9 elements, even if the table size indicator display properly 6.  How to maintain the initial cluster size when converting to and then since then, a table?

  The f

  Well, if you have worked with context-sensitive help running you would see:

  "With the right button of the function and select the Size of Cluster in the context menu to set the number of items in the cluster."

  The default is new. The maximum cluster size for this function is 256. »

  You must set the size. There is no way for the function to know how many elements in the table.

• The problem of the distribution of the data in the cluster of NoSQL Oracle databases

  Hello

  I write (about 10 G) data in an Oracle Databae NoSQL cluster (which consists of three nodes: ud1, Node2, node3). It has only one table in the DB and I create an index on a field.

  The amount of data in each node is about 16G.

  Then I write the same data (about 10G) in an Oracle NoSQL Database (Only one node) and I create an index on the same lot.

  But the amount of data is about 46G.

  So I assumed that each node holds no data complete. Then if the failure of a node, the cluster can still work but some data cannot be queried. Am I wrong?

  There is an intersection in the form of database on each node?

  You should take a look at the documentation. For example:

  http://docs.Oracle.com/CD/NoSQL/HTML/AdminGuide/introduction.html

  -mark

• How to display the number of socket in the ListBox UI control?

  I want to display the number of socket in the Listbox control on execution. I use DisplayExpression method, set the entry as '% TestSocketIndex', but it does not work. This methond works fine if I connect the Combobox of UI control to ExecutionViewMgr.ConnectExecutionList.

  Is there a solution

  

  

  Hey wellsc,

  I have looked at this issue and ran into the same issue you described. I dropped the CAR 482840 for a developer study the matter further. Unfortunately, workarounds only I can think immediately would be to use a ComboBox control or to implement the functionality desired by using a native LabVIEW ListBox.

  Let us know if there is something we can do to help, or if you have other questions about how to implement one of the workarounds. You can still use this CAR number to check the status of the issue, as well.