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On the HP Discover in June 2013 (I wrote 2014, sorry for that typo). HP has announced the HP 3PAR StoreServ 7450 All-Flash Array. To optimize the StoreServ platform for all-flash workloads, HP made some changes to the hardware of the nodes. The 7450 uses 8-core Intel Xeon CPUs instead 6-core 1.8 Ghz CPUs, the cache was doubled from 64GB to 128GB and they added some changes to the 3PAR OS: HP added additional cache flush queues to separate the flushing of cache for rotating rust and SSD devices. They also made some write I/O optimizations and added the ability to perform fragmented writes. Instead of writing 16 KB blocks, 3PAR OS is now able to write only 4 KB of a 16 KB block. This software-based changes may be used also on the 7200 and 7400. This leads to the new…

This is only a short blog post. Just got an e-mail from the DataCore Support. They found a critical bug in SANsymphony-V 10.0.0.0 which should be fixed with Update 1. Only VMware customers are affected, because the bug is related to VMware Thin Provisioning Thresholds. Update 1 is planned for early September 2014. If you’re running SANsymphony-V 10.0.0.0 open an incident at the DataCore Support to get an available hotfix. If you have planned to update to SANsymphony-V 10, delay this update until the release of SANsymphony-V 10 Update 1.

The developtment of the Intelligent Resilient Framework (IRF) goes back to H3C, a joint venture between Huawai and 3COM. With the acquisition of 3COM by HP, IRF capable products were integrated into the HP Networking product portfolio.

What is IRF?

IRF is a software-based solution to connect multiple switches together and create a logical switching devices. The idea behind IRF is to create a logical device with one control and multiple data planes. This simplifies the management and sometimes eliminates the need for technics like (R/M)STP, XRRP/ VRRP/ HSRP or similar, to create layer 2 or layer 3 redundancy for cases like a switch failure. This depends on the requirements of the network design. The master switch in an IRF stack updates the forwarding and routing table for all devices in the stack. If it fails, another switch in the stack is elected. The switches are connected with multiple high speed links (10 GbE in most cases, some entry-level switches allow 1 GbE) and use a daisy chain or ring topology. If a switch fails, even if it’s the master of the stack, the stack will operate continuously. The time for a failover is < 50ms (Source). There are another advantage: Because the stack acts like a single switch, you can use switch-assisted teaming or trunking between IRF stacks or between servers and IRF stacks.

Sometimes it’s necessary to limit specific traffic in terms of bandwidth. Today I like to show you how to manage bandwidth limits using QoS and firewall policies. Especially if you have only limited bandwidth, e.g. a DSL connection, it can be useful to manage the used bandwidth for specific hosts or protocols. I use a really simple setup to show you, how you can manage bandwidth using CoS on a Juniper SRX.

Virtualization is an awesome technology. Last weeks I visited a customer and we took a walk through their data centers. While standing in one of their data centers I thought: Imagine that all server, that they are currently run as VMs, would be physical?. I’m still impressed about the influence of virtualization. The idea is so simple You share the resources of the physical hardware between multiple virtual instances. I/O, network bandwidth, CPU cycles and memory. After nearly 10 years of experience with server virtualization I can tell that especially the memory resources is one of the weak points. When a customer experiences performance problems, they were mostly caused by a  lack of storage I/O or memory.

Everyone has their own technique to organize work. As you maybe know, I’m a big fan of Lean. And you know maybe also, that Lean is a philosophy based on the aspect to create value for customers and eliminate waste of resources in production processes. Taiichi Ōno, the father of the Toyota productionsystem, defined seven forms of waste. Womack and Jones developed Lean Production, which is based on TPS, and highlighted five principles to achieve a lean production.

I’m a bit late, but HP released a new version of their HP Service Pack for ProLiant in June 2014. This version of the SPP supersedes the version 2014.02.0(B). This release adds support for HPs new 20 GbE adapter

• HP FlexFabric 20Gb 2-port 630FLB Adapter
• HP FlexFabric 20Gb 2-port 630M Adapter

and contains new firmware (v4.20b) for HP BladeSystem c-Class Virtual Connect, 4/8Gb 20-port and 8Gb 24-port FC components. HP also added the following firmware and software components to this release:

Today I stumbled over a nice workaround. While installing a CentOS 6 VM, I needed to install the VMware Tools. I don’t know why, but I got an error message, regarding a non accessible VMware Tools ISO.

I remembered a blog post I read a few months ago, about a VMware online repository, from which VMware tools can be installed. You can download the repository information here. The RPM for RHEL can also be used for CentOS. Simply download and install the RPM:

When moving users to Exchange 2013 it can happen, that they can’t access public folders housed on the old Exchange 2010 or 2007 server. The same can happen to shared mailboxes (mailboxes with Full Access permissions). The users are constantly prompted for credentials or they get this message:

Cannot expand the folder. Microsoft Exchange is not available. Either there are network problems or the Exchange server is down for maintenance.

There is an advantage, if you solves problems: You can learn something. I’m currently migrate a small Exchange 2007 environment to Exchange 2013. The first thing I learnt was, that IT staff still uses their own accounts for administration, and sometimes they assign administrator rights to users for testing and troubleshooting purposes. This can be a problem, as I described in my last posting. Today I learnt something different: Sometimes it’s the little things that bring you to despair.