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NetApp has offered Data ONTAP for some time in two flavours:

• 7-Mode
• Clustered Data ONTAP (cDOT)

With cDOT, NetApp has rewritten ONTAP nearly from scratch. The aim was to create an Storage OS, that leverages scale-out architecture and storage virtualization techniques, as well as providing non-disruptive operations. NetApp has needed some release cycles to get cDOT at that point, where it provides all features that customers know from 7-Mode. With Data ONTAP 8.3, NetApp has reached this point. Even Metrocluster is now supported. That’s a huge improvement and I’m glad that NetApp has made it. But NetApp wasted no time in cutting off old habits: With ONTAP 8.3, 7-Mode is no longer offered. Okay, no big deal. Customers can migrate from 7-Mode to cDOT. Yes, indeed. But it’s not that easy as you maybe think.

In my last blog post I have highlighted how HAProxy can be used to distribute client connections to two or more servers with Exchange 2013 CAS role. But there is another common use case for load balancers in a Exchange environment: SMTP. Let’s take a look at this drawing:

The inbound SMTP connections are distributed to two Mail Transfer Agents (often a cluster of appliances, like Cisco IronPort or Symantec Messaging Gateway) and the MTAs forward the e-mails to the Exchange servers. Sometimes the e-mails are not directly forwarded to the Exchange servers, but to mail security appliances instead (like Zertificon Z1 SecureMail Gateway). After the e-mails have been processed by the mail security appliances, they are forwarded to the Exchange backend. Such setups are quite common. If a load balancer isn’t used, the MX records often point to the public IP address of a specific MTA. In this case, two or more MX records have to be set to ensure that e-mails can be received, even if a MTA fails.

Since Exchange 2007 client connections are handled by the Client Access Server role. With Exchange 2010, Microsoft has introduced the concept of the Client Access Server Array (CAS Array). A CAS Array is required, when internal and external client connections should be load balanced over multiple client access servers. Many client access protocols in Exchange 2010 require session affinity. This means, that the connection between the client and a particular client access server must persist. This requires application-level load balancing for Exchange 2010 and Microsoft recommends this explicitly. Microsoft dropped the concept of the CAS Array in Exchange 2013 and implemented much more logic into the Exchange 2013 Client Access Server role. There is no more need for session affinity in any client access protocol used in Microsoft Exchange 2013. Connections to a Exchange 2013 client access servers can be directed to an available server. A simple DNS round-robin works, but if a server fails, DNS would not handle this.You can use Windows Network Load Balancing (WNLB), but it has several limitations and downsides. I blogged about one of them in my blog post Flooded network due HP Networking Switches & Windows NLB. The other point is, that you can’t use it when you build a two server CAS/ DAG Exchange 2013 environment: You can’t use WNLB on servers that have the Microsoft Failover Cluster role installed. At this point HAProxy comes into play.

A VMware vSphere cluster is nothing without shared storage. Most of the functions, like VMware HA or VMware vMotion (okay, vMotion is possible without shared storage), can only be used with a shared storage. The servers in my lab have Fibre Channel Host Bus Adapters (HBA), but buying an old and cheap Fibre Channel storage system wasn’t an option in my case. This left two options when choosing the right storage protocol: iSCSI or NFS. I tried to virtualize the local storage in my ProLiants with the HP StoreVirtual VSA and DataCore SANsymphony-V, but both were too complex for my needs and a lab environment. Because of this I decided to move the local storage into a small storage system and use iSCSI or NFS. I searched for a while for a suiteable system until Chris Wahl started blogging about the Synology DS414slim.

The next step is to connect the Synology DS414slim to my lab network. I use two HP 1910 Switches in my lab, a 8 Port and a 24 Port model. The Synology DS414slim has two 1 GbE ports, which can configured in different ways. I wanted to use both ports actively, to I decided to create a bond.

Create a bond

Browse to the admin website and go to Control Panel > Network > Network Interfaces and select “Create”. Then select “Create Bond”.

This blog post covers the setup of the volumes and shares. Depending on your disk config, variuos volume configurations are possible. The DS414slim supports all important RAID levels (Synology Hybrid RAID, Basic, JBOD, RAID 0, 1, 5, 6 and 10). I recommend to use RAID 5, if you use more then two disks. I decided to create a RAID 5 with my three Crucial M550 SSDs and use the Seagate Momentus XT as a single disk.

Chris Wahl wrote a good blog post about the VAAI-NAS plugin some days ago. I really recommend to read this posting. Because of his article, I will only describe the installation of the plugin. You can download the plugin on the Synology homepage for free.

There are two ways to install the plugin: With the vSphere Update Manager (VUM) and a host extension baseline, or with ESXCLI.

Plugin installation using the vSphere Update Manager

First of all, we need to import the plugin (host extension) to the patch repository. Open the vSphere C# client, switch to the “Home” screen and click “Update Manager” under “Solutions and Applications”. Switch to the “Patch Repository” tab and click “Import Patches”.

VMware presented the vRealize Operations Manager 6.0 at the VMworld 2014 in Barcelona. In early december, vROps was available for download.

vROps 6.0 is the successor of VMwares IT Operations Management suite vCenter Operations Manager, or vCOps. VMware has aligned the naming scheme with other products, so this release is the first release under the new brand vRealize.

VMware has made some major improvements to this release. One of the biggest advantages is the ability to scale-out. In prior releases you had to deploy multiple vApps to scale. Now you can add additional vROps instances to a cluster. These appliances provide computing resources, as well as redundancy. This allows you to scale beyond the limits of vCOps 5. Redundancy is provided by a concept which is based on master, replica and data nodes. The fist node in a vROps deployment is the master node. By adding a replica node, you can add redundancy for the case that the master node fails. Master and replica node work in a active/ standby relationship. The data nodes are the secret behind the scalability of vROps. A data node has only one task to perform: Collect data based on the assigned adapter.

Part 1 of this series has covered a short overview over vRealize Operations Manager 6.0 and the initial deployment of the virtual appliance. Now it’s time to bring it to life.

Open a browser and enter the IP of your newly deployed vROps appliance. You will get this nice initial setup screen. “New Installation” is always a good start. Click “New Installation”.

I wrote about what’s new in vROps 6 and about the deployment of the virtual appliance. I also described how to migrate the data from the old vCOps vApp. Part 3 covers the decommission of the old vApp.

Enter the IP or FQDN of your UI VM into the browser. Login as admin into the administration UI.

Before the vApp can be removed, the vCOps needs to be unregistered from the vCenter. Click “Unregister”.