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Some days ago I talked to a colleague from our sales team and we discussed different solutions for a customer. I will spare you the details, but we discussed different solutions and we came across PernixData FVP, HP 3PAR Adaptive Optimization, HP 3PAR Adaptive Flash Cache and DataCore SANsymphony-V. And then the question of all questions came up: “What is the difference?”.

Simplify, then add Lightness

Lets talk about tiering. To make it simple: Tiering moves a block from one tier to another, depending on how often a block is accessed in a specific time. A tier is a class of storage with specific characteristics, for example ultra-fast flash, enterprise-grade SAS drives or even nearline drives. Characteristics can be the drive type, the used RAID level or a combination of characteristics. A 3-tier storage design can consist of only one drive type, but they can be organized in different RAID levels. Tier 1 can be RAID 1 and tier 3 can be RAID 6, but all tiers use enterprise-grade 15k SAS drives. But you can also mix drive types and RAID levels, for example tier 1 with flash, tier 2 with 15k SAS in a RAID 5 and tier 3 with SAS-NL and RAID 6. Each time a block is accessed, the block “heats up”. If it’s hot enough, it is moved one tier up. If it’s less often accessed, the block “cools down” and at a specific point, the block is moved a tier down. If a tier is full, colder blocks will to be moved down and hotter block have to be moved up. It’s a bit simplified, but products like DataCore SANsymphony-V with Auto-Tiering or HP 3PAR Adaptive Optimization are working this way.

A customer of mine is currently refreshing his branch office server infrastructure. A part of this project is to demote the Active Directory Domain Controllers, that are currently running in each branch office. The customer has multiple branch offices and each branch office has an Active Directory Domain Controller which is acting as file-/ print- and DHCP server. Each branch office has its own Active Directory site. The Domain Controller and the used IP subnets are assigned to the corresponding AD site. Due to this configuration the clients at the branch office choose the site-local Domain Controller as logon server. This works totally flawless since a couple of years. Over the year bandwidth of site connection has increased and even small branch offices have a redundant MPLS connection to the HQ. And no one likes single domain AD forests with 20 or more Domain Controllers…

Some days ago a colleague and I implemented a small 3-node VMware vSphere Essentials Plus cluster with a HP 3PAR StoreServ 7200c. Costs are always a sore point in SMB environments, so it should not surprise that we used iSCSI in this design. I had some doubt about using iSCSI with a HP 3PAR StoreServ, mostly because of the performance and complexity. IMHO iSCSI is more complex to implement then Fibre Channel (FC). But in this case I had to deal with it.

Sometimes you have to update the OS of your DataCore Storage Server, or the server is crashed and you have to reinstall it. In both cases, a configuration backup is the starting point. The procedure remains the same, regardless if it’s an update or a reinstall after a server crash:

• Install Windows Server OS
• Copy configuration backup file to C:\Program Files\DataCore\SANsymphony\Recovery
• Install DataCore SANsymphony-V

Take a backup

You can take the configuration backup on different ways:

On February 25, 2015 PernixData released the latest version of PernixData FVP. Even if it’s only a .5 release, FVP 2.5 adds some really cool features and improvements. New features are:

• Distributed Fault Tolerant Memory-Z (DFTM-Z)
• Intelligent I/O profiling
• Role-based access control (RBAC), and
• Network acceleration for NFS datastores

Distributed Fault Tolerant Memory-Z (DFTM-Z)

FVP 2.0 introduced support for server side memory as an acceleration resources. With this it was possible to use server side memroy to accelerate VM I/O operations. Server side memory is faster then flash, but also more expensive. With FVP 2.5, the support for adaptive memory compression. was added. DFTM-Z provides a more efficient use of the expensive resource “server side memory”.  Some of you may think “Oh no, compression! This will only cost performance!”. I don’t think that this is fair. ;) The PernixData engineers are focused on performance and I think that they haven’t during the development of DFTM-Z. DFTM-Z is enabled on hosts that use at least 20 GB memory for FVP. With increasing memory used for FVP, the area used for compression in the memory is also increased. So not the whole memory area used for acceleration is compressed, it’s only a part of it. With 20 GB contributing the FVP cluster, the compressed memory region is 4 GB. With more than 160 GB, the region is increased to 32 GB.

A customer of mine had within 6 months twice a full database partition on a VMware vCenter Server Appliance. After the first outage, the customer increased the size of the partition which is mounted to /storage/db. Some months later, some days ago, the vCSA became unresponsive again. Again because of a filled up database partition. The customer increased the size of the database partition again  (~ 200 GB!!) and today I had time to take a look at this nasty vCSA.

If you are a frequent reader of virtualization blogs, then you may have heard about the vLaunchPad. It lists hundreds of VMware & virtualization blogs, as well as links to resources and other material. The vLaunchPad is managed by Eric Siebert (@ericsiebert, vsphere-land.com) and he organizes year for year the annual Top vBlog voting contest. This year the Top vBlog contest is sponsored by Infinio.

In the 2014 voting my “old” blog was voted on place 292 of 320. I should mention that blazilla.de had only german-language content. In a community, where english is the predominating content language, this result may not surprise. If you are interested in last year’s results, you can find them here. In 2014 I have started vcloudnine.de, but I didn’t nominated it for the 2014 voting. Instead, I nominated blazilla.de for the Top vBlog 2014 contest. This year the tables turned and I have nominated vcloudnine.de for the categories:

The VMware vExpert is a given title from VMware to individuals who have significantly contributed to the community and have spread the message of VMware to customers and partners worldwide. This is nothing you get by passing an exam. It’s given to you by VMware in respect of your work. The vExpert title is something which differates you inside the commnity. Individuals who participate in the program, have access to betas, free licenses, early access briefings, free access to VMworld conference materials online, access to a private community, use of logos etc.

Yesterday I’ve updated a CentOS 6.6 VM with a simple yum update. A couple of packages were updated and to be honest: I haven’t checked which packages were updated. Today I noticed that an application, that uses a secure tunnel to connect to another application, doesn’t work. While browsing through the log files, I found this message from Stunnel.

LOG3[1145:140388919940864]: SSL_accept: 14076129: error:14076129:SSL routines:SSL23_GET_CLIENT_HELLO:only tls allowed in fips mode

I rised the debug level and restarted Stunnel. Right after the restart, I found this in the logs.

Disk space is rare. I only have about 1 TB of SSD storage in my lab and I don’t like to waste too much of it. My hosts use NFS to connect to my Synology NAS, and even if I use the VAAI-NAS plugin, I use thin-provisioned disks only. Thin-provisioned disks tend to grow over time. If you copy a 1 GB file into a VM and you delete this file immediately, you will find that the VMDK is increased by 1 GB. This is caused by the guest filesystem. It marks the blocks of deleted files as free, even if it only deletes metadata and not the data itself. Later, the data is overwritten with new data, since the blocks are marked as free and the new data is written in there. VMware ESXi doesn’t know that the guest has marked blocks as free. So ESXi can’t shrink the thin-provisioned VMDK.