HP iLO 4 Firmware Issues

Recently there has been an issue raised with HP that in rare  instances,  on a ProLiant Gen8 series server with HP Integrated Lights-Out 4 (iLO 4) Firmware Versions 1.30, 1.32, 1.40 or 1.50, intermittent Non-Maskable Interrupt (NMI) events may occur. After rebooting the server, the operating system loads properly and no additional impact to system operation will occur. If this issue occurs, the operating system will indicate that an NMI has happened; however, the specific indication will vary by OS: VMware ESXi operating systems will experience a Purple Screen of Death (PSOD). Linux operating systems will display a message indicating that…
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Wyse Thin client Daylight Saving issue

I had an interesting problem that appeared shortly after the GMT Daylight saving time changed on Sunday evening (31st March) with Wyse Xenith/Xenith2 thin client devices which are used to access a Citrix VDI environment delivering a Windows 7 Professional desktop to around 800 users. So what was the issue? The problem was reported that even though the clock went forward 1 hour the Windows 7 clients where reporting that the time hadn’t changed (gone forward) since the change.  People were not turning up to meeting on time and it caused mayhem. Taking a look at the time zone set on the Windows 7…
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Symantec NetBackup and PureDisk appliances

This may be off topic but I thought I would cover it anyway as a colleague of mine found the information very useful.  We had a faulty 1TB disk (in slot 16) which needed replacing but looking at the front of the appliance there was no indication/labels to give us a clue as to location of  slot 16.  We trawled the internet for hours and finally came up with the following diagrams that perhaps one day may help you out and save you many hours of surfing. Following tables show the location of hotspare disks and data disks in different models…
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EMC Clarrion faulting devices

Whilst doing a physical inspection of our datacentre today I noticed that we had multiple disk enclosures indicating an amber warning light.  After checking Navisphere (and after picking myself up of the floor) I noticed the following errors. As you can see from the diagram six disk enclosures had faulted. (more…)
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MetaLUNs Explained

The purpose of a MetaLUN is that a Clariion can grow the size of a LUN on the ‘fly’. Let’s say that a host is running out of space on a LUN. From Navisphere, we can “Expand” a LUN by adding more LUNs to the LUN that the host has access to. To the host, we are not adding more LUNs. All the host is going to see is that the LUN has grown in size. We will explain later how to make space available to the host. (more…)
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Disable TCP Chimney offload

When it comes to the virutalisation , there are considerations for performance. There are options which are enabled by default which makes sense for laptops and even desktops. A VM, however, may not benefit and in fact may see performance loss. One such feature is TCP Chimney offload. TCP Chimney offload is designed to free up CPU utilization and increase network throughput by moving TCP processing tasks to hardware. This frees up the server’s CPU for other tasks. This makes sense if consider the available processors, ram and types of tasks running. Chances are a VM is only performing a…
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What is RAID?

I've had a number of emails asking me to provide details about RAID well here goes I think I've covered everything. RAID is a group of independent physical disks that provides high performance by increasing the number of drives used for saving and accessing data. A RAID disk subsystem improves I/O performance and data availability. The physical disk group appears to the host system either as a single storage unit or multiple logical units. Data throughput improves because several disks are accessed simultaneously. RAID systems also improve data storage availability and fault tolerance. Data loss caused by a physical disk failure…
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