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  • SQL Server and Hyper-V Dynamic Memory - Part 1

    - by SQLOS Team
    SQL and Dynamic Memory Blog Post Series   Hyper-V Dynamic Memory is a new feature in Windows Server 2008 R2 SP1 that allows the memory assigned to guest virtual machines to vary according to demand. Using this feature with SQL Server is supported, but how well does it work in an environment where available memory can vary dynamically, especially since SQL Server likes memory, and is not very eager to let go of it? The next three posts will look at this question in detail. In Part 1 Serdar Sutay, a program manager in the Windows Hyper-V team, introduces Dynamic Memory with an overview of the basic architecture, configuration and monitoring concepts. In subsequent parts we will look at SQL Server memory handling, and develop some guidelines on using SQL Server with Dynamic Memory.   Part 1: Dynamic Memory Introduction   In virtualized environments memory is often the bottleneck for reaching higher VM densities. In Windows Server 2008 R2 SP1 Hyper-V introduced a new feature “Dynamic Memory” to improve VM densities on Hyper-V hosts. Dynamic Memory increases the memory utilization in virtualized environments by enabling VM memory to be changed dynamically when the VM is running.   This brings up the question of how to utilize this feature with SQL Server VMs as SQL Server performance is very sensitive to the memory being used. In the next three posts we’ll discuss the internals of Dynamic Memory, SQL Server Memory Management and how to use Dynamic Memory with SQL Server VMs.   Memory Utilization Efficiency in Virtualized Environments   The primary reason memory is usually the bottleneck for higher VM densities is that users tend to be generous when assigning memory to their VMs. Here are some memory sizing practices we’ve heard from customers:   ·         I assign 4 GB of memory to my VMs. I don’t know if all of it is being used by the applications but no one complains. ·         I take the minimum system requirements and add 50% more. ·         I go with the recommendations provided by my software vendor.   In reality correctly sizing a virtual machine requires significant effort to monitor the memory usage of the applications. Since this is not done in most environments, VMs are usually over-provisioned in terms of memory. In other words, a SQL Server VM that is assigned 4 GB of memory may not need to use 4 GB.   How does Dynamic Memory help?   Dynamic Memory improves the memory utilization by removing the requirement to determine the memory need for an application. Hyper-V determines the memory needed by applications in the VM by evaluating the memory usage information in the guest with Dynamic Memory. VMs can start with a small amount of memory and they can be assigned more memory dynamically based on the workload of applications running inside.   Overview of Dynamic Memory Concepts   ·         Startup Memory: Startup Memory is the starting amount of memory when Dynamic Memory is enabled for a VM. Dynamic Memory will make sure that this amount of memory is always assigned to the VMs by default.   ·         Maximum Memory: Maximum Memory specifies the maximum amount of memory that a VM can grow to with Dynamic Memory. ·         Memory Demand: Memory Demand is the amount determined by Dynamic Memory as the memory needed by the applications in the VM. In Windows Server 2008 R2 SP1, this is equal to the total amount of committed memory of the VM. ·         Memory Buffer: Memory Buffer is the amount of memory assigned to the VMs in addition to their memory demand to satisfy immediate memory requirements and file cache needs.   Once Dynamic Memory is enabled for a VM, it will start with the “Startup Memory”. After the boot process Dynamic Memory will determine the “Memory Demand” of the VM. Based on this memory demand it will determine the amount of “Memory Buffer” that needs to be assigned to the VM. Dynamic Memory will assign the total of “Memory Demand” and “Memory Buffer” to the VM as long as this value is less than “Maximum Memory” and as long as physical memory is available on the host.   What happens when there is not enough physical memory available on the host?   Once there is not enough physical memory on the host to satisfy VM needs, Dynamic Memory will assign less than needed amount of memory to the VMs based on their importance. A concept known as “Memory Weight” is used to determine how much VMs should be penalized based on their needed amount of memory. “Memory Weight” is a configuration setting on the VM. It can be configured to be higher for the VMs with high performance requirements. Under high memory pressure on the host, the “Memory Weight” of the VMs are evaluated in a relative manner and the VMs with lower relative “Memory Weight” will be penalized more than the ones with higher “Memory Weight”.   Dynamic Memory Configuration   Based on these concepts “Startup Memory”, “Maximum Memory”, “Memory Buffer” and “Memory Weight” can be configured as shown below in Windows Server 2008 R2 SP1 Hyper-V Manager. Memory Demand is automatically calculated by Dynamic Memory once VMs start running.     Dynamic Memory Monitoring    In Windows Server 2008 R2 SP1, Hyper-V Manager displays the memory status of VMs in the following three columns:         ·         Assigned Memory represents the current physical memory assigned to the VM. In regular conditions this will be equal to the sum of “Memory Demand” and “Memory Buffer” assigned to the VM. When there is not enough memory on the host, this value can go below the Memory Demand determined for the VM. ·         Memory Demand displays the current “Memory Demand” determined for the VM. ·         Memory Status displays the current memory status of the VM. This column can represent three values for a VM: o   OK: In this condition the VM is assigned the total of Memory Demand and Memory Buffer it needs. o   Low: In this condition the VM is assigned all the Memory Demand and a certain percentage of the Memory Buffer it needs. o   Warning: In this condition the VM is assigned a lower memory than its Memory Demand. When VMs are running in this condition, it’s likely that they will exhibit performance problems due to internal paging happening in the VM.    So far so good! But how does it work with SQL Server?   SQL Server is aggressive in terms of memory usage for good reasons. This raises the question: How do SQL Server and Dynamic Memory work together? To understand the full story, we’ll first need to understand how SQL Server Memory Management works. This will be covered in our second post in “SQL and Dynamic Memory” series. Meanwhile if you want to dive deeper into Dynamic Memory you can check the below posts from the Windows Virtualization Team Blog:   http://blogs.technet.com/virtualization/archive/2010/03/18/dynamic-memory-coming-to-hyper-v.aspx   http://blogs.technet.com/virtualization/archive/2010/03/25/dynamic-memory-coming-to-hyper-v-part-2.aspx   http://blogs.technet.com/virtualization/archive/2010/04/07/dynamic-memory-coming-to-hyper-v-part-3.aspx   http://blogs.technet.com/b/virtualization/archive/2010/04/21/dynamic-memory-coming-to-hyper-v-part-4.aspx   http://blogs.technet.com/b/virtualization/archive/2010/05/20/dynamic-memory-coming-to-hyper-v-part-5.aspx   http://blogs.technet.com/b/virtualization/archive/2010/07/12/dynamic-memory-coming-to-hyper-v-part-6.aspx   - Serdar Sutay   Originally posted at http://blogs.msdn.com/b/sqlosteam/

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  • SQL Server and Hyper-V Dynamic Memory - Part 1

    - by SQLOS Team
    SQL and Dynamic Memory Blog Post Series   Hyper-V Dynamic Memory is a new feature in Windows Server 2008 R2 SP1 that allows the memory assigned to guest virtual machines to vary according to demand. Using this feature with SQL Server is supported, but how well does it work in an environment where available memory can vary dynamically, especially since SQL Server likes memory, and is not very eager to let go of it? The next three posts will look at this question in detail. In Part 1 Serdar Sutay, a program manager in the Windows Hyper-V team, introduces Dynamic Memory with an overview of the basic architecture, configuration and monitoring concepts. In subsequent parts we will look at SQL Server memory handling, and develop some guidelines on using SQL Server with Dynamic Memory.   Part 1: Dynamic Memory Introduction   In virtualized environments memory is often the bottleneck for reaching higher VM densities. In Windows Server 2008 R2 SP1 Hyper-V introduced a new feature “Dynamic Memory” to improve VM densities on Hyper-V hosts. Dynamic Memory increases the memory utilization in virtualized environments by enabling VM memory to be changed dynamically when the VM is running.   This brings up the question of how to utilize this feature with SQL Server VMs as SQL Server performance is very sensitive to the memory being used. In the next three posts we’ll discuss the internals of Dynamic Memory, SQL Server Memory Management and how to use Dynamic Memory with SQL Server VMs.   Memory Utilization Efficiency in Virtualized Environments   The primary reason memory is usually the bottleneck for higher VM densities is that users tend to be generous when assigning memory to their VMs. Here are some memory sizing practices we’ve heard from customers:   ·         I assign 4 GB of memory to my VMs. I don’t know if all of it is being used by the applications but no one complains. ·         I take the minimum system requirements and add 50% more. ·         I go with the recommendations provided by my software vendor.   In reality correctly sizing a virtual machine requires significant effort to monitor the memory usage of the applications. Since this is not done in most environments, VMs are usually over-provisioned in terms of memory. In other words, a SQL Server VM that is assigned 4 GB of memory may not need to use 4 GB.   How does Dynamic Memory help?   Dynamic Memory improves the memory utilization by removing the requirement to determine the memory need for an application. Hyper-V determines the memory needed by applications in the VM by evaluating the memory usage information in the guest with Dynamic Memory. VMs can start with a small amount of memory and they can be assigned more memory dynamically based on the workload of applications running inside.   Overview of Dynamic Memory Concepts   ·         Startup Memory: Startup Memory is the starting amount of memory when Dynamic Memory is enabled for a VM. Dynamic Memory will make sure that this amount of memory is always assigned to the VMs by default.   ·         Maximum Memory: Maximum Memory specifies the maximum amount of memory that a VM can grow to with Dynamic Memory. ·         Memory Demand: Memory Demand is the amount determined by Dynamic Memory as the memory needed by the applications in the VM. In Windows Server 2008 R2 SP1, this is equal to the total amount of committed memory of the VM. ·         Memory Buffer: Memory Buffer is the amount of memory assigned to the VMs in addition to their memory demand to satisfy immediate memory requirements and file cache needs.   Once Dynamic Memory is enabled for a VM, it will start with the “Startup Memory”. After the boot process Dynamic Memory will determine the “Memory Demand” of the VM. Based on this memory demand it will determine the amount of “Memory Buffer” that needs to be assigned to the VM. Dynamic Memory will assign the total of “Memory Demand” and “Memory Buffer” to the VM as long as this value is less than “Maximum Memory” and as long as physical memory is available on the host.   What happens when there is not enough physical memory available on the host?   Once there is not enough physical memory on the host to satisfy VM needs, Dynamic Memory will assign less than needed amount of memory to the VMs based on their importance. A concept known as “Memory Weight” is used to determine how much VMs should be penalized based on their needed amount of memory. “Memory Weight” is a configuration setting on the VM. It can be configured to be higher for the VMs with high performance requirements. Under high memory pressure on the host, the “Memory Weight” of the VMs are evaluated in a relative manner and the VMs with lower relative “Memory Weight” will be penalized more than the ones with higher “Memory Weight”.   Dynamic Memory Configuration   Based on these concepts “Startup Memory”, “Maximum Memory”, “Memory Buffer” and “Memory Weight” can be configured as shown below in Windows Server 2008 R2 SP1 Hyper-V Manager. Memory Demand is automatically calculated by Dynamic Memory once VMs start running.     Dynamic Memory Monitoring    In Windows Server 2008 R2 SP1, Hyper-V Manager displays the memory status of VMs in the following three columns:         ·         Assigned Memory represents the current physical memory assigned to the VM. In regular conditions this will be equal to the sum of “Memory Demand” and “Memory Buffer” assigned to the VM. When there is not enough memory on the host, this value can go below the Memory Demand determined for the VM. ·         Memory Demand displays the current “Memory Demand” determined for the VM. ·         Memory Status displays the current memory status of the VM. This column can represent three values for a VM: o   OK: In this condition the VM is assigned the total of Memory Demand and Memory Buffer it needs. o   Low: In this condition the VM is assigned all the Memory Demand and a certain percentage of the Memory Buffer it needs. o   Warning: In this condition the VM is assigned a lower memory than its Memory Demand. When VMs are running in this condition, it’s likely that they will exhibit performance problems due to internal paging happening in the VM.    So far so good! But how does it work with SQL Server?   SQL Server is aggressive in terms of memory usage for good reasons. This raises the question: How do SQL Server and Dynamic Memory work together? To understand the full story, we’ll first need to understand how SQL Server Memory Management works. This will be covered in our second post in “SQL and Dynamic Memory” series. Meanwhile if you want to dive deeper into Dynamic Memory you can check the below posts from the Windows Virtualization Team Blog:   http://blogs.technet.com/virtualization/archive/2010/03/18/dynamic-memory-coming-to-hyper-v.aspx   http://blogs.technet.com/virtualization/archive/2010/03/25/dynamic-memory-coming-to-hyper-v-part-2.aspx   http://blogs.technet.com/virtualization/archive/2010/04/07/dynamic-memory-coming-to-hyper-v-part-3.aspx   http://blogs.technet.com/b/virtualization/archive/2010/04/21/dynamic-memory-coming-to-hyper-v-part-4.aspx   http://blogs.technet.com/b/virtualization/archive/2010/05/20/dynamic-memory-coming-to-hyper-v-part-5.aspx   http://blogs.technet.com/b/virtualization/archive/2010/07/12/dynamic-memory-coming-to-hyper-v-part-6.aspx   - Serdar Sutay   Originally posted at http://blogs.msdn.com/b/sqlosteam/

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  • RAID 10 or RAID 5 for multiple VMs - what is the best choice?

    - by Lars Fastrup
    I have just ordered a new rig for my business. We do a lot of software development for Microsoft SharePoint and need the rig to run several virtual machines for development and test purposes. We will be using the free VMware ESXi for virtualization. For a start, we plan to build and start the following VMs - all with Windows Server 2008 R2 x64: Active Directory server MS SQL Server 2008 R2 Automated Build Server SharePoint 2010 Server for hosting our public Web site and our internal Intranet for a few people. The load on this server is going to be quite insignificant. 2xSharePoint 2007 development server 2xSharePoint 2010 development server Beyond that we will need to build several SharePoint farms for testing purposes. These VMs will only be started when needed. The specs of the new rig is: Dell R610 rack server 2xIntel XEON E5620 48GB RAM 6x146GB SAS drives Dell H700 RAID controller We believe the new server is going to make our VMs perform a lot better than our existing setup (2xIntel XEON, 16GB RAM, 2x500 GB SATA in RAID 1). But we are not sure about the RAID level for the new rig. Should we go for having the the 6x146GB SAS drives in a RAID 10 configuration or a RAID 5 configuration? RAID 10 seems to offer better write performance and lower risk of a RAID failure. But it comes at a cost of less drive space. Do we need RAID 10 or would RAID 5 also be a good choice for us?

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  • Reasons to Use a VM For Development

    - by George Stocker
    Background: I work at a start-up company, where one team uses Virtual Machines to connect to a remote server to do their development, and another team (the team I'm on) uses local IIS/SQL Server 2005/Visual Studio installations to conduct work. Team VM is located about 1000 miles from Team Non-VM, and the servers the VMs run off of are located near Team VM (Latency, for those that are wondering, is about 50ms). A person high in the company is pushing for Team Non-VM to use virtual machines for programming, development, and testing. The latter point we agree on -- we want Virtual Machines to test configurations and various aspects of the web application in a 'clean' state. The Problem: What we don't agree on is having developers using RDP to connect to a desktop remotely that contains Visual Studio, SQL Server, and IIS to do the same development we could do locally on our laptops. I've tried the VM set-up, and besides the color issue, there is a latency issue that is rather noticeable, not to mention that since we're a start-up, a good number of employees work from home on occasion with our work laptops, and this move would cut off the laptops. They'd be turned in. Reasons to Use Remote VMs for Development (Not Testing!): Here are the stated reasons that this person wants us to use VMs: They work for TeamVM. They keep the source code "safe". If we want to work from home, we could just use our home PCs. Licenses (I don't know what the argument is, only that it's been used). Reasons not to use Remote VMs for Development: Here are the stated reasons why we don't want to use VMs: We like working from home. We get a lot done on our own time. We're not going to use our Home PCs to do work related stuff. The Latency is noticeable. Support for the VMs (if they go down, or if we need a new VM) takes a while. We don't have administrative privileges on the VM, and are unable to change settings as needed. What I'm looking for from the community is this: What reasons would you give for not using VMs for development? Keep in mind these are remote VMs -- this isn't a VM running on a local desktop. It's using the laptop (or a desktop) as a thin client for a remote VM. Also, on the other side of the coin: Is there something we're missing that makes VMs more palatable for development? Edit: I think 'safe' is used in term of corporate espionage, or more correctly if the Laptop gets stolen, the person who stole would have access to our source code. The former (as we've pointed out, is always going to be a possibility -- companies stop that with litigation, there isn't a technical solution (so far as I can see)). The latter point is ( though I don't know its usefulness in a corporate scenario) mitigated by Truecrypt'ing the entire volume.

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  • Reasons to Use a VM For Development

    - by George Stocker
    Background: I work at a start-up company, where one team uses Virtual Machines to connect to a remote server to do their development, and another team (the team I'm on) uses local IIS/SQL Server 2005/Visual Studio installations to conduct work. Team VM is located about 1000 miles from Team Non-VM, and the servers the VMs run off of are located near Team VM (Latency, for those that are wondering, is about 50ms). A person high in the company is pushing for Team Non-VM to use virtual machines for programming, development, and testing. The latter point we agree on -- we want Virtual Machines to test configurations and various aspects of the web application in a 'clean' state. The Problem: What we don't agree on is having developers using RDP to connect to a desktop remotely that contains Visual Studio, SQL Server, and IIS to do the same development we could do locally on our laptops. I've tried the VM set-up, and besides the color issue, there is a latency issue that is rather noticeable, not to mention that since we're a start-up, a good number of employees work from home on occasion with our work laptops, and this move would cut off the laptops. They'd be turned in. Reasons to Use Remote VMs for Development (Not Testing!): Here are the stated reasons that this person wants us to use VMs: They work for TeamVM. They keep the source code "safe". If we want to work from home, we could just use our home PCs. Licenses (I don't know what the argument is, only that it's been used). Reasons not to use Remote VMs for Development: Here are the stated reasons why we don't want to use VMs: We like working from home. We get a lot done on our own time. We're not going to use our Home PCs to do work related stuff. The Latency is noticeable. Support for the VMs (if they go down, or if we need a new VM) takes a while. We don't have administrative privileges on the VM, and are unable to change settings as needed. What I'm looking for from the community is this: What reasons would you give for not using VMs for development? Keep in mind these are remote VMs -- this isn't a VM running on a local desktop. It's using the laptop (or a desktop) as a thin client for a remote VM. Also, on the other side of the coin: Is there something we're missing that makes VMs more palatable for development? Edit: I think 'safe' is used in term of corporate espionage, or more correctly if the Laptop gets stolen, the person who stole would have access to our source code. The former (as we've pointed out, is always going to be a possibility -- companies stop that with litigation, there isn't a technical solution (so far as I can see)). The latter point is ( though I don't know its usefulness in a corporate scenario) mitigated by Truecrypt'ing the entire volume.

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  • Regulating outgoing traffic on ubuntu VM

    - by DazSlayer
    I am making a virtual network setup for my high school cybersecurity team to practice. I am connecting all the VMs together through a VPN and then people who are practicing will VPN in and ssh/remote desktop into the different VMs. The problem is that for practicing, they will need root access into the VMs and because the VMs are connecting to my personal network, the VMs pose a security risk to my personal network. Is there any way in either VMWare or VirtualBox or even making an unchangeable iptable (I can make all the windows VMs go thru a linux VM) to prevent people from connecting to my local network via the VM?

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  • Just a few questions about Hyper-V virtual machines and clustering

    - by René Kåbis
    I have been using Microsoft’s Hyper-V technology for a little while now, but I am just now dipping my toe into clustering. In particular, I am trying to implement a fault-tolerant SQL DB. This involves setting up two VMs, clustering them via Failover Cluster, and then installing SQL Server in some fashion. I have two physical machines - one high-end and rather beefy “heavy lifter” to contain the majority of the VMs, and another “backup” (a repurposed desktop) to hold the essential “secondary” (or failover) AD-DC, SQL and FS VMs. The main reason why I find the failover cluster at the VM level so attractive is that it presents a single IP and DNS entry to the network as a whole - if one machine (physical or virtual) goes down, you might loose some ping and the connections get reset, but the network applications (Microsoft RMS connection to backend SQL) can still connect to a viable DB without having to mess around with the settings at all. My first question is in terms of SQL Server itself. If I have a cluster between two VMs, does it make more sense to install the SQL Server in Failover Cluster configuration or should I simply install it in a stand-alone config and mirror the DBs? For example, this post suggests just mirroring the DBs, but do I just mirror standalone DBs on standalone VMs, or can I get the network and failover benefits of clustered VMs while still utilizing (on each clustered VM) standalone DBs that have been mirrored between each other? As well, I have come across a lot of documentation about SQL clustering, but most assume a number (#2) of physical machines to hold not only the actual SQL VMs but also the Quorum and Witness stores. I will not be able to muster more than two physical machines. As such, I will have to be satisfied with a VM cluster that does not exceed two VMs (one for each physical machine). Another issue involves MSDTC - the Distributed Transaction Coordinator. When attempting to install the SQL Failover Cluster (I never completed it for this reason) it threw a hissy fit because MSDTC had not been clustered. Search as I might, I have not yet found a way to do so under Windows Server 2012 R2. I have found plenty of docs for Windows 2008 and 2008 R2, but these instructions don’t align with 2012 R2 (at least, not in a way that allows me to successfully cluster MSDTC). Plus, some of the instructions that I have found for SQL Server Failover Cluster installation suggest that a third “network device” - shared network storage (a SAN) - is required for the DB itself (and other functionality). I do not have this, and won’t be getting this. Most of my storage exists on the “heavy lifter” that was designed for all of the “primary” VMs. If that physical machine goes down, so does the storage. The secondary server does have enough resources for an AD-DC Server, an SQL server and a File Server, so it will handle the “secondary” failover versions of those VMs (clustered or not). My final question involves file servers. If I cluster file servers between two VMs (one on my “heavy lifter” and another on my “backup”, how do I mirror the data between them? Clustering VMs only provides a single point of access on the network for a resource, it doesn’t exactly replicate data between the two - that is left to the services that serve up that data. I am unsure how I can ensure that file server data between two clustered file server VMs can be properly mirrored. Remember, I only have two devices to be used here - my primary machine and a backup secondary. There is no chance of me obtaining a SAN or any other type of network attached storage. What exists on the machines must act as the storage. Thanks in advance for any suggestions.

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  • Should I consolidate multiple identical VMs into BSD jails?

    - by Josh
    We run a number of Openfire XMPP/Jabber servers. Due to the way Openfire works, we cannot easily run multiple Openfire instances on one server, so I have 5 identical VMware ESXi VMs, each with CentOS, MySQl, Java, and Openfire. They're the exact same, except for their IP addresses, the actual Openfire MySQL database and it's config file. I am wondering if this is the optimal configuration, or if it would be better to move these VMs to a single FreeBSD machine and put each one inside a FreeBSD jail. Specifically, I am wondering if the benefit of VMWare's Transparent Page Sharing (TPS) would outweight the cost of running 5 identical OSes. Would I end up using less memory with one large FreeBSD machine and java running in bsd jails?

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  • Quick and dirty user management service for Linux VMs?

    - by quack quixote
    Background I have a home server running Debian, and a workstation that runs various VirtualBox VMs (mostly Linuxen but some Windows). At the moment, I'm creating my main user account anew for every new Linux VM. I'd like to make use of a centralized user-management scheme instead, so I can just configure the new VMs for the directory technology and let them handle user lookups automatically. The last time I worked with anything like this, NIS+ was still in fashion. I have a vague notion of what LDAP and Active Directory are, but no knowledge of how to configure them for what I want. Question What user-management/network-directory technology should I use for providing user accounts to my network? The server must run on Debian Lenny. Client configuration should be simple point-at-server-and-go. I need an example configuration for one sample user account. (nice-to-have) I may want to mount the user's home directory from the server. (nice-to-have) The same configuration works with Windows clients.

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  • Dell PowerEdge 2950 III running XenServer with 2 VMs gets sluggish after a week and needs rebooted?

    - by Joshua Rountree
    It has weird hangs and then random CPU spikes that do a ton at once. While remoted into the VMs I get an update all at once then it hangs for another 20 seconds. When it lets it go through I get a CPU spike. Basic server specs for the HW node is: 8 CPUs, 16GB ram 1TB HDD total iPERC6 raid 10 The VMs are barely used but I have them spec'd at VM 1: 4 CPUs, 4GB Ram VM2: 4 CPUs 6GB ram The HW node currently says it's total CPU usage is 11% AND Used Memory is at 63%out of 16GB I'm new to this stuff so I'm not sure. I just recently installed this and set it all up. Please advise if you can!

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  • What is the best way to setup a heartbeat agent for failover between two VMs?

    - by EGr
    I have two VMs in VirtualBox that use NAT for their network adapters. They are both getting the same IP address, so I will need to reconfigure that; but knowing that, is it possible to set up a heartbeat agent to failover an apache server if one of the two VMs go down? The way I pictured it would be that the webserver would be able to be accessed externally via :80. No matter what VM was running, I would be able to access the website at that IP/port since failover would be setup. I'm running into trouble setting up IPs when the network adapters are set to NAT, and people have told me that I shouldn't be setting the IPs in this configuration. So what should I do to achieve what I'm looking for? Is it even feasible?

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  • parallel vms in VMWare Server - how to configure network so they can ping each other?

    - by IronGoofy
    I'm using VMWare Server (currently on Version 1.0.7) and have two VMs that I would like to run at the same time. However, I'm having problems in setting them up so they can ping each other. I've configured them to use 'Bridged' networking. They both obtain an IP address from the DHCP server on my network, but after that they can't ping each other. It seems that only the first one has a functioning network connection (I can ping it from the host machine and Internet connection works), but the other one does not. If it helps, both VMs are running XP SP 3. Any ideas? Thanks!

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  • Recovering a VHD after resizing it using VBoxManage

    - by tjrobinson
    I am using VirtualBox 4.1.18 and had a virtual machine running Windows 8 RC with a single VHD, which was initially sized at 25GB (too small!). After installing the OS and some applications I ran out of disk space so shut down the guest and then used this command to resize the VHD to 80GB: C:\Program Files\Oracle\VirtualBox> .\VBoxManage.exe modifyhd "D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vhd" --resize 81920 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100% C:\Program Files\Oracle\VirtualBox> .\VBoxManage.exe showhdinfo "D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vhd" UUID: 03fb26e7-d8bb-49b5-8cc2-1dc350750e64 Accessible: yes Logical size: 81920 MBytes Current size on disk: 24954 MBytes Type: normal (base) Storage format: VHD Format variant: dynamic default In use by VMs: Windows 8 RC (UUID: a6e6aa57-2d3a-421b-8042-7aae566e3e0b) Location: D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vhd So far so good. However, when I started the guest up again I got the dreaded: Fatal: No bootable medium found! system halted If I boot into GParted it shows a single 80GB drive as "unallocated". The option to scan for and attempt to repair a filesystem doesn't find anything. I also tried cloning the VHD into a VDI file, just in case that magically fixed it: C:\Program Files\Oracle\VirtualBox> .\VBoxManage.exe clonehd "D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vhd" "D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vdi" --format VDI 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100% Clone hard disk created in format 'VDI'. UUID: baf0c2c4-362f-4f6c-846a-37bb1ffc027b C:\Program Files\Oracle\VirtualBox> .\VBoxManage.exe showhdinfo "D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vdi" UUID: baf0c2c4-362f-4f6c-846a-37bb1ffc027b Accessible: yes Logical size: 81920 MBytes Current size on disk: 24798 MBytes Type: normal (base) Storage format: VDI Format variant: dynamic default In use by VMs: Windows 8 RC (UUID: a6e6aa57-2d3a-421b-8042-7aae566e3e0b) Location: D:\VirtualBox VMs\Windows 8 RC\Windows 8 RC.vdi Is there anything else I could try to recover the drive? No, I don't have a backup :( My host OS is Windows 7 64-bit.

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  • Creating and using VM Groups in VirtualBox

    - by Fat Bloke
    With VirtualBox 4.2 we introduced the Groups feature which allows you to organize and manage your guest virtual machines collectively, rather than individually. Groups are quite a powerful concept and there are a few nice features you may not have discovered yet, so here's a bit more information about groups, and how they can be used.... Creating a group Groups are just ad hoc collections of virtual machines and there are several ways of creating a group: In the VirtualBox Manager GUI: Drag one VM onto another to create a group of those 2 VMs. You can then drag and drop more VMs into that group; Select multiple VMs (using Ctrl or Shift and click) then  select the menu: Machine...Group; or   press Cmd+U (Mac), or Ctrl+U(Windows); or right-click the multiple selection and choose Group, like this: From the command line: Group membership is an attribute of the vm so you can modify the vm to belong in a group. For example, to put the vm "Ubuntu" into the group "TestGroup" run this command: VBoxManage modifyvm "Ubuntu" --groups "/TestGroup" Deleting a Group Groups can be deleted by removing a group attribute from all the VMs that constitute that group. To do this via the command-line the syntax is: VBoxManage modifyvm "Ubuntu" --groups "" In the VirtualBox Manager, this is more easily done by right-clicking on a group header and selecting "Ungroup", like this: Multiple Groups Now that we understand that Groups are just attributes of VMs, it can be seen that VMs can exist in multiple groups, for example, doing this: VBoxManage modifyvm "Ubuntu" --groups "/TestGroup","/ProjectX","/ProjectY" Results in: Or via the VirtualBox Manager, you can drag VMs while pressing the Alt key (Mac) or Ctrl (other platforms). Nested Groups Just like you can drag VMs around in the VirtualBox Manager, you can also drag whole groups around. And dropping a group within a group creates a nested group. Via the command-line, nested groups are specified using a path-like syntax, like this: VBoxManage modifyvm "Ubuntu" --groups "/TestGroup/Linux" ...which creates a sub-group and puts the VM in it. Navigating Groups In the VirtualBox Manager, Groups can be collapsed and expanded by clicking on the carat to the left in the Group Header. But you can also Enter and Leave groups too, either by using the right-arrow/left-arrow keys, or by clicking on the carat on the right hand side of the Group Header, like this: . ..leading to a view of just the Group contents. You can Leave or return to the parent in the same way. Don't worry if you are imprecise with your clicking, you can use a double click on the entire right half of the Group Header to Enter a group, and the left half to Leave a group. Double-clicking on the left half when you're at the top will roll-up or collapse the group.   Group Operations The real power of Groups is not simply in arranging them prettily in the Manager. Rather it is about performing collective operations on them, once you have grouped them appropriately. For example, let's say that you are working on a project (Project X) where you have a solution stack of: Database VM, Middleware/App VM, and  a couple of client VMs which you use to test your app. With VM Groups you can start the whole stack with one operation. Select the Group Header, and choose Start: The full list of operations that may be performed on Groups are: Start Starts from any state (boot or resume) Start VMs in headless mode (hold Shift while starting) Pause Reset Close Save state Send Shutdown signal Poweroff Discard saved state Show in filesystem Sort Conclusion Hopefully we've shown that the introduction of VM Groups not only makes Oracle VM VirtualBox pretty, but pretty powerful too.  - FB 

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  • i5 540M or i7 720QM for laptop running VMs and software development tools?

    - by Donald Hughes
    I'm a software developer that would primarily be running Windows 7 as the primary operating system. On a typical day, I might, at any given moment, be running Visual Studio, Expression Web, SQL Server developer (and Management Console), IIS, Photoshop, a dozen browser tabs in 2-3 different browsers, Skype video chat, streaming music, and a couple of VMs (WinXP and Ubuntu) for testing/experimentation. Obviously, RAM is a concern, which is why I plan to use 8 GB so I can devote enough to the VMs to be usable. I'm also tempted to use an ExpressCard SSD for storing the VM disks to ease disk contention. And I know that that is asking a lot from a laptop, and I should just use a desktop, but I need to be able to take my work with me between several locations. It seems that at a reasonable price point, it comes down to the i5 540M versus the i7 720QM. I'm leaning toward the i7 since it would allow me to dedicate a whole hyperthreaded core to each VM, and still have two cores left for the primary OS. I've heard that the i5 has better battery life, but I'm curious for my scenario if there would be a meaningful difference. I don't usually work without a plug, but I do occasionally ride the train or fly and it would be nice to have at least 3 hours of juice for unusual circumstances. And, finally, for this usage scenario, would a dedicated video option be preferred over the i5's integrated video? It sounds like Visual Studio 2010 (and Windows 7) can take advantage of the video card.

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  • How do I back up Hyper-V VMs with Windows Server backup on Windows Server 2008 R2?

    - by Chris
    I've searched this site and google, and I CAN find information about how to back up Hyper-V virtual machines by using Windows Server Backup from the Hyper-V host in Windows Server 2008. You have to set up a registry key to enable the Hyper-V VSS writer, and then you can take online backups of your VMs. However, all the information I have found is about a year old, and none of it has been updated for Windows Server 2008 R2. I tried to run the "FixIt" .msi found here: http://support.microsoft.com/kb/958662 ... but it said that it was not applicable to my operating system. So I am thinking either Windows Server 2008 R2 already has its VSS service for Hyper-V enabled, or it still needs to be enabled but the FixIt package doesn't feel comfortable operating on an OS that wasn't RTM at the time. I went ahead and scheduled a windows server backup for 9pm tomorrow. It said it would take 86 GB, which means it MUST be counting those VMs. But will this backup fail? Can anyone confirm whether you have to apply the same registry changes for R2?

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  • SQL Server and Hyper-V Dynamic Memory Part 3

    - by SQLOS Team
    In parts 1 and 2 of this series we looked at the basics of Hyper-V Dynamic Memory and SQL Server memory management. In this part Serdar looks at configuration guidelines for SQL Server memory management. Part 3: Configuration Guidelines for Hyper-V Dynamic Memory and SQL Server Now that we understand SQL Server Memory Management and Hyper-V Dynamic Memory basics, let’s take a look at general configuration guidelines in order to utilize benefits of Hyper-V Dynamic Memory in your SQL Server VMs. Requirements Host Operating System Requirements Hyper-V Dynamic Memory feature is introduced with Windows Server 2008 R2 SP1. Therefore in order to use Dynamic Memory for your virtual machines, you need to have Windows Server 2008 R2 SP1 or Microsoft Hyper-V Server 2008 R2 SP1 in your Hyper-V host. Guest Operating System Requirements In addition to this Dynamic Memory is only supported in Standard, Web, Enterprise and Datacenter editions of windows running inside VMs. Make sure that your VM is running one of these editions. For additional requirements on each operating system see “Dynamic Memory Configuration Guidelines” here. SQL Server Requirements All versions of SQL Server support Hyper-V Dynamic Memory. However, only certain editions of SQL Server are aware of dynamically changing system memory. To have a truly dynamic environment for your SQL Server VMs make sure that you are running one of the SQL Server editions listed below: ·         SQL Server 2005 Enterprise ·         SQL Server 2008 Enterprise / Datacenter Editions ·         SQL Server 2008 R2 Enterprise / Datacenter Editions Configuration guidelines for other versions of SQL Server are covered below in the FAQ section. Guidelines for configuring Dynamic Memory Parameters Here is how to configure Dynamic Memory for your SQL VMs in a nutshell: Hyper-V Dynamic Memory Parameter Recommendation Startup RAM 1 GB + SQL Min Server Memory Maximum RAM > SQL Max Server Memory Memory Buffer % 5 Memory Weight Based on performance needs   Startup RAM In order to ensure that your SQL Server VMs can start correctly, ensure that Startup RAM is higher than configured SQL Min Server Memory for your VMs. Otherwise SQL Server service will need to do paging in order to start since it will not be able to see enough memory during startup. Also note that Startup Memory will always be reserved for your VMs. This will guarantee a certain level of performance for your SQL Servers, however setting this too high will limit the consolidation benefits you’ll get out of your virtualization environment. Maximum RAM This one is obvious. If you’ve configured SQL Max Server Memory for your SQL Server, make sure that Dynamic Memory Maximum RAM configuration is higher than this value. Otherwise your SQL Server will not grow to memory values higher than the value configured for Dynamic Memory. Memory Buffer % Memory buffer configuration is used to provision file cache to virtual machines in order to improve performance. Due to the fact that SQL Server is managing its own buffer pool, Memory Buffer setting should be configured to the lowest value possible, 5%. Configuring a higher memory buffer will prevent low resource notifications from Windows Memory Manager and it will prevent reclaiming memory from SQL Server VMs. Memory Weight Memory weight configuration defines the importance of memory to a VM. Configure higher values for the VMs that have higher performance requirements. VMs with higher memory weight will have more memory under high memory pressure conditions on your host. Questions and Answers Q1 – Which SQL Server memory model is best for Dynamic Memory? The best SQL Server model for Dynamic Memory is “Locked Page Memory Model”. This memory model ensures that SQL Server memory is never paged out and it’s also adaptive to dynamically changing memory in the system. This will be extremely useful when Dynamic Memory is attempting to remove memory from SQL Server VMs ensuring no SQL Server memory is paged out. You can find instructions on configuring “Locked Page Memory Model” for your SQL Servers here. Q2 – What about other SQL Server Editions, how should I configure Dynamic Memory for them? Other editions of SQL Server do not adapt to dynamically changing environments. They will determine how much memory they should allocate during startup and don’t change this value afterwards. Therefore make sure that you configure a higher startup memory for your VM because that will be all the memory that SQL Server utilize Tune Maximum Memory and Memory Buffer based on the other workloads running on the system. If there are no other workloads consider using Static Memory for these editions. Q3 – What if I have multiple SQL Server instances in a VM? Having multiple SQL Server instances in a VM is not a general recommendation for predictable performance, manageability and isolation. In order to achieve a predictable behavior make sure that you configure SQL Min Server Memory and SQL Max Server Memory for each instance in the VM. And make sure that: ·         Dynamic Memory Startup Memory is greater than the sum of SQL Min Server Memory values for the instances in the VM ·         Dynamic Memory Maximum Memory is greater than the sum of SQL Max Server Memory values for the instances in the VM Q4 – I’m using Large Page Memory Model for my SQL Server. Can I still use Dynamic Memory? The short answer is no. SQL Server does not dynamically change its memory size when configured with Large Page Memory Model. In virtualized environments Hyper-V provides large page support by default. Most of the time, Large Page Memory Model doesn’t bring any benefits to a SQL Server if it’s running in virtualized environments. Q5 – How do I monitor SQL performance when I’m trying Dynamic Memory on my VMs? Use the performance counters below to monitor memory performance for SQL Server: Process - Working Set: This counter is available in the VM via process performance counters. It represents the actual amount of physical memory being used by SQL Server process in the VM. SQL Server – Buffer Cache Hit Ratio: This counter is available in the VM via SQL Server counters. This represents the paging being done by SQL Server. A rate of 90% or higher is desirable. Conclusion These blog posts are a quick start to a story that will be developing more in the near future. We’re still continuing our testing and investigations to provide more detailed configuration guidelines with example performance numbers with a white paper in the upcoming months. Now it’s time to give SQL Server and Hyper-V Dynamic Memory a try. Use this guidelines to kick-start your environment. See what you think about it and let us know of your experiences. - Serdar Sutay Originally posted at http://blogs.msdn.com/b/sqlosteam/

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  • PowerShell Script to Deploy Multiple VM on Azure in Parallel #azure #powershell

    - by Marco Russo (SQLBI)
    This blog is usually dedicated to Business Intelligence and SQL Server, but I didn’t found easily on the web simple PowerShell scripts to help me deploying a number of virtual machines on Azure that I use for testing and development. Since I need to deploy, start, stop and remove many virtual machines created from a common image I created (you know, Tabular is not part of the standard images provided by Microsoft…), I wanted to minimize the time required to execute every operation from my Windows Azure PowerShell console (but I suggest you using Windows PowerShell ISE), so I also wanted to fire the commands as soon as possible in parallel, without losing the result in the console. In order to execute multiple commands in parallel, I used the Start-Job cmdlet, and using Get-Job and Receive-Job I wait for job completion and display the messages generated during background command execution. This technique allows me to reduce execution time when I have to deploy, start, stop or remove virtual machines. Please note that a few operations on Azure acquire an exclusive lock and cannot be really executed in parallel, but only one part of their execution time is subject to this lock. Thus, you obtain a better response time also in these scenarios (this is the case of the provisioning of a new VM). Finally, when you remove the VMs you still have the disk containing the virtual machine to remove. This cannot be done just after the VM removal, because you have to wait that the removal operation is completed on Azure. So I wrote a script that you have to run a few minutes after VMs removal and delete disks (and VHD) no longer related to a VM. I just check that the disk were associated to the original image name used to provision the VMs (so I don’t remove other disks deployed by other batches that I might want to preserve). These examples are specific for my scenario, if you need more complex configurations you have to change and adapt the code. But if your need is to create multiple instances of the same VM running in a workgroup, these scripts should be good enough. I prepared the following PowerShell scripts: ProvisionVMs: Provision many VMs in parallel starting from the same image. It creates one service for each VM. RemoveVMs: Remove all the VMs in parallel – it also remove the service created for the VM StartVMs: Starts all the VMs in parallel StopVMs: Stops all the VMs in parallel RemoveOrphanDisks: Remove all the disks no longer used by any VMs. Run this script a few minutes after RemoveVMs script. ProvisionVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   # Name of storage account (where VMs will be deployed) $StorageAccount = "Copy the Label property you get from Get-AzureStorageAccount"   function ProvisionVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName) $Location = "Copy the Location property you get from Get-AzureStorageAccount" $InstanceSize = "A5" # You can use any other instance, such as Large, A6, and so on $AdminUsername = "UserName" # Write the name of the administrator account in the new VM $Password = "Password"      # Write the password of the administrator account in the new VM $Image = "Copy the ImageName property you get from Get-AzureVMImage" # You can list your own images using the following command: # Get-AzureVMImage | Where-Object {$_.PublisherName -eq "User" }         New-AzureVMConfig -Name $VmName -ImageName $Image -InstanceSize $InstanceSize |             Add-AzureProvisioningConfig -Windows -Password $Password -AdminUsername $AdminUsername|             New-AzureVM -Location $Location -ServiceName "$VmName" -Verbose     } }   # Set the proper storage - you might remove this line if you have only one storage in the subscription Set-AzureSubscription -SubscriptionName $SubscriptionName -CurrentStorageAccount $StorageAccount   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list provisions one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed ProvisionVM "test10" ProvisionVM "test11" ProvisionVM "test12" ProvisionVM "test13" ProvisionVM "test14" ProvisionVM "test15" ProvisionVM "test16" ProvisionVM "test17" ProvisionVM "test18" ProvisionVM "test19" ProvisionVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup of jobs Remove-Job *   # Displays batch completed echo "Provisioning VM Completed" RemoveVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function RemoveVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Remove-AzureService -ServiceName $VmName -Force -Verbose     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list remove one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed RemoveVM "test10" RemoveVM "test11" RemoveVM "test12" RemoveVM "test13" RemoveVM "test14" RemoveVM "test15" RemoveVM "test16" RemoveVM "test17" RemoveVM "test18" RemoveVM "test19" RemoveVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Remove VM Completed" StartVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function StartVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Start-AzureVM -Name $VmName -ServiceName $VmName -Verbose     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list starts one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed StartVM "test10" StartVM "test11" StartVM "test11" StartVM "test12" StartVM "test13" StartVM "test14" StartVM "test15" StartVM "test16" StartVM "test17" StartVM "test18" StartVM "test19" StartVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Start VM Completed"   StopVMs # Name of subscription $SubscriptionName = "Copy the SubscriptionName property you get from Get-AzureSubscription"   function StopVM( [string]$VmName ) {     Start-Job -ArgumentList $VmName {         param($VmName)         Stop-AzureVM -Name $VmName -ServiceName $VmName -Verbose -Force     } }   # Select the subscription - this line is fundamental if you have access to multiple subscription # You might remove this line if you have only one subscription Select-AzureSubscription -SubscriptionName $SubscriptionName   # Every line in the following list stops one VM using the name specified in the argument # You can change the number of lines - use a unique name for every VM - don't reuse names # already used in other VMs already deployed StopVM "test10" StopVM "test11" StopVM "test12" StopVM "test13" StopVM "test14" StopVM "test15" StopVM "test16" StopVM "test17" StopVM "test18" StopVM "test19" StopVM "test20"   # Wait for all to complete While (Get-Job -State "Running") {     Get-Job -State "Completed" | Receive-Job     Start-Sleep 1 }   # Display output from all jobs Get-Job | Receive-Job   # Cleanup Remove-Job *   # Displays batch completed echo "Stop VM Completed" RemoveOrphanDisks $Image = "Copy the ImageName property you get from Get-AzureVMImage" # You can list your own images using the following command: # Get-AzureVMImage | Where-Object {$_.PublisherName -eq "User" }   # Remove all orphan disks coming from the image specified in $ImageName Get-AzureDisk |     Where-Object {$_.attachedto -eq $null -and $_.SourceImageName -eq $ImageName} |     Remove-AzureDisk -DeleteVHD -Verbose  

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  • how to make a script for esxi vms rebooting process.

    - by user116374
    I'm Using ESXi 5.0 And I have created a lab for metasploit. one time my system exploited, so i have to restart my vms. so it's too much Headache. i have to execute lots of exploit. so i don't want to do the same restart process again and again. so maybe it is possible through the script. so again im stuck. I don't know how to write a script for this process. PLEASE tell me how to write a script for AUTOMATION restart process in 10 20 minute. And how to execute that script. Please Share your knowledge if you know. this script thing is very very useful for me. And also tell me any other way if you know. Ty. Alen.

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  • What is the best backup solution for VMware Infrastructure system that hosts a wide variety of VMs?

    - by SBWorks
    In a situation where you are running: VMware Infrastructure 4.x with multiple hosts Over 150 VMs with a wide variety of operating systems (Linux in a half dozen distros, Solaris, every MS version, etc.) in multiple languages with almost every mix of installed software (luckily, no Exchange mail servers) Using an EMC fiber channel SAN The VWs that need need to be backed up use about 2 terabytes of data (total) The goal is to keep backups for about 3-months At this rough scale, what backup solutions have worked well for you? And, as an add-on question, did any of them have de-duplication that you thought was effective and useful?

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  • Hyper-V and host-installed hardware devices: can guest VMs access?

    - by gravyface
    Have a couple of servers I'd like to setup as Hyper-V Servers, with a couple of Windows 2008 Standard VMs. On the host, we have a few hardware devices we'd like to be accessible to the guest; I'm not sure if these are supported via a raw "pass-thru" on Hyper-V (which I don't have alot of experience with) if the same drivers are installed on the guest. Hardware in question is a Brooktrout fax card, a SCSI adapter for the tape drive, and a 9-pin serial connected to one of the core firewalls for management.

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