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Finally, the idea of running a Disaster Recovery test is manageable. VMware Site Recovery Manager combined with vSphere has made it possible to test a failover to a warm site without worrying that the DR test itself will cause an outage. Setting up Site Recovery Manager and performing a site failover sounds like a daunting task, but VMware has made this very simple, assuming you are familiar with vSphere already. If you already have a virtual environment setup at both your production site and a secondary site, SRM is pretty simple to get started with but allows for almost any DR Plan you can think of to be run. ...

A question often comes up about what to do when you have a segmented virtual network that needs to be able to traverse subnets. This might happen if you’re doing some testing and don’t want the machines to contact the production network, or perhaps doing a test SRM failover and having the virtual machines in their own test network. Virtual machines in subnet (A) might need to contact other virtual machines in subnet (B) but don’t have access to the physical router any longer, so they can’t communicate. To solve this issue, how about we try a virtual router? ...

We’re probably all aware of the benefits of clustering things like SQL Server in order to provide highly available data. But shared storage clustering has some drawbacks on VMware ESXi clusters such as not being able to vMotion. • Database Mirroring – SQL Server database mirrors utilize a non-shared storage availability solution, using built-in SQL Server replication technology to create and maintain one or more copies of each database on other SQL Servers in the environment. SQL Server database mirrors provide application-aware availability, and the lack of a quorum disk makes this a VMware-friendly solution, allowing the full use of vMotion, DRS, and HA. ...

One of my most frequently read articles is on how to use MBRAlign to align your virtual machine disks on Netapp storage. Well, after Netapp has released their new Virtual Storage Console (VSC4) the tedious task of using MBRAlign might be eased for some admins. Optimization and Migration The new VSC4 console for vSphere has a new tab called Optimization and Migration. Here you are able to scan all or some of your datastores to check the alignment of your virtual machines. The scan manager can even be set on a schedule so that changes to the datastore will be recognized. ...

Many services such as DHCP or TFTP use broadcast packets to find a particular server. In the case of DHCP, a device when connecting to a network will send out a broadcast to find a DHCP server to get an IP address to use. But what if you have multiple subnets on your network? You could have a DHCP server on each of your subnets, but this seems a bit overkill. ...

Hewlett-Packard has released the details of their new product line the Gen8 (don’t call me G8) servers. The new line as, you would expect, has all of the performance increases that seem necessary when coming out with a new product. The new Sandy Bridge XEON processors are onboard, they’ve increased the number of DIMM slots, increased the total amount of memory allowed per system while also increasing the memory speed supported. HP has also switched over to PCI 3.0 which is providing much faster speeds for PCI devices. ...

If you’ve built a virtual infrastructure you’ve probably had to decide whether or not to use Beacon Probing when setting up your vSwitch uplink ports. But what is it, and why do we need it? Let me propose a scenario. Assume that we have a virtual switch with three uplinks, and one of those uplinks fails. If the uplinks are setup correctly, they will see the failed uplink and start sending their frames over the other active uplinks. This is standard network fault tolerance from vSphere. ...

Determining which type of RAID to use when building a storage solution will largely depend on two things; capacity and performance. Performance is the topic of this post. We measure disk performance in IOPS or Input/Output per second. One read request or one write request = 1 IO. Each disk in you storage system can provide a certain amount of IO based off of the rotational speed, average latency and average seek time. I’ve listed some averages for each type of disk below. ...

VMware has lots of ways to setup networking on their ESXi hosts. In order to set this up in the best way for your needs, it’s important to understand how the traffic will be routed between VMs, virtual switches, physical switches and physical network adapters. Before looking at an example, we should review some networking 101. Machines on the same vlan on the same switch can communicate with one another (assuming there is no firewall type devices in the way). Machines on different vlans on the same switch cannot communicate unless the traffic passes through a router. ...

Zoning and Lun Masking are often confused for each other, probably because both of them are used to restrict access to storage. They should both be used to secure the storage network and reduce unnecessary traffic. Zoning If you want to specify only certain hosts from accessing a storage device then you would want to setup zoning. For instance, in the example below, you can see that the two servers on the right can access three of the four storage devices, whereas the two on the left can only access two of the SANs. This configuration is done on the Fibre Channel switch. iSCSI, NFS, and FCoE can also be segmented, but they would use typical TCPIP segmentation methods like setting up a VLAN. ...