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Introduction to Fibre Channel (FC) If you are new to Fibre Channel SAN technology you should take the time to familiarise yourself with the basic terminology. Fibre Channel (FC) was developed in the late 1980s and became an American National Standards Institute (ANSI) standard in 1994 with it’s physical topology as well as logical topology and protocols are all defined by the ANSI T11 standard. As the name suggests, it was designed to be based on fibre optic cabling as the physical transport to overcome some of the limitations of the SCSI physical layer. Fibre Channel can actually run on copper cables over short distances, where Fibre Channel can easily go 10KM. A storage area network (SAN) is a specialised high-speed network that connects host servers to high-performance storage subsystems. The SAN components include host bus adapters (HBAs) in the host servers, switches that help route storage traffic, cables, storage…

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In this blog we will learn how to change the Round Robin Path Selection Policy (VMW_PSP_RR) on FC and iSCSI LUNs in a VMware environment to better balance the I/O load across all active storage paths. Modifying the IOPS limitation to 1 will improve performance where an active storage path might have several queued I/Os. In addition, setting the limitation to 1 allows other active storage paths to service I/O requests.  This will have the benefit of reduced latency and increased throughput. ESXi Round Robin PSP supports two types of limits: IOPS limit: The Round Robin PSP defaults to an IOPS limit with a value of 1000. In this default case, a new path is used after 1000 I/O operations are issued. Bytes limit: The bytes limit is an alternative to the IOPS limit. The bytes limit allows for a specified amount of bytes to be transferred before the path…

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I’ve been running Plex in a CentOS 7 VM for over 5 years and it’s been extremely stable, I’ve had no issues, not even one. Currently Plex is hosted on VMware ESXi 7.0.2 host with two 4 vCPUs and 6GB of vRAM and it works well with H264. I’ve decided to re-rip all of my blu-rays and then transcode them to H265 which will give me a better quality file that takes less space than the same file in H264 takes. When I need to transcode video to sync to a mobile device for a trip or transcode H265 to H264 for devices that don’t support H265 the processor consumes a lot of CPU on the VM. I could just add more vCPUs to the VM but I have a limit on how many vCPUs I have, and there are more efficient ways to transcode video. I did some research…

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The Scope I’m going to setup Fibre Channel storage network to connect ESXi 7 hosts to a TrueNAS Core storage server using a Cisco MDS series switch. I’ve chosen to use Fibre Channel for my VM datastores because of it’s great performance and reliability and the fact that it works so well with VMware ESXi. Fibre Channel will connect the TrueNAS Core storage server (target) and ESXi servers (initiator) over a fabric. In this setup, I’ve got one Cisco MDS DS-C9148-16p-K9 switch, two Dell R720 ESXi 7 servers and one TrueNAS storage server. All of the servers will have QLogic HBAs with link a speed of 8Gbs. I will create 2 logical networks using VSAN’s to replicate having to separate switches. Although the Cisco MDS 9148-16p-K9 switch has 48 Fibre Channel ports, only 16 of them can acquire port a license by default and the remaining ports have to be activated…

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I’ve been looking for a way to control a standard AC ceiling fan for some time. I use Z-Wave products for my lighting control and unfortunately there are no Z-Wave fan controllers that I know of. The main prerequisite is that the fan speed can be controlled from a wall plate independent of Home Assistant this will make sure that like the lights the fans would still be operational in the event Home Assistant crashes. In this blog I will show you how I achieved this goal with a little modification to the code and recompile of the firmware. We need to change the way the relays are switched from the default way Slow (1) – relay 1 on 2 & 3 off Medium (2) relay 1 & 2 on 3 off Fast (3) relay 3 on 1 & 2 off This behaviour does not give the correct speed control.…

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I’ve been running the VMs in my home lab on a ZFS pool on FreeNAS and now TruneNAS CORE made up of 600GB 10K SAS drives in a 6 x 2 way mirror configuration for some time and it works fine, but I’ve always wanted to have an all SSD high performance array. The price for used 400GB Hitachi Ultrastar SSD400M HUSML4040ASS600 has finally fallen to a level that makes them an option for a home lab setup. These were some of the best SAS SSDs available when they were released and they still have lots to offer for the home user. These drivers are MLC NAND with supper high endurance. For the rest of this blog when ever I say TrueNAS I’m referring to TrueNAS CORE the replacement for FreeNAS the free open source NAS.

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Eventually you will come to the point where you’ll need more storage. I’m running TrueNAS and there are 3 main ways of increasing storage capacity. You could replace every disc in the pool to a larger size, one disc at a time resilvering each disc as you go and once all discs are replaced the pool will have grown in size. The second option is to add another vdev to the pool and last create another pool. I’m using a Dell R620 with 12 3.5″ bays and have no available slots in my server for more discs so after some time looking at the options I decided to go with 2 x EMC DAE. DAE stands for Disk Array Enclosure. There are two different types, one with 25 2.5″ slots and the one I’ve chosen to use, the KTN-STL3 which has 15 3.5″ slots with SAS 2 controllers.

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The first thing you need when going down the rabbit hole of setting a smart home with all the bells and whistles is a server to safely hold all of your data and a way to share that data. A server can be any computer that can serve up one or more applications, it could be a Raspberry PI to run Home Assistant or and enterprise server with lots of processing power, memory, storage and connectivity. If you are only running one application then the Raspberry PI would do but if like me you want to run many resource hungry applications like Plex and Zoneminder with facial and object recognition then a server in the traditional sense is needed.

There are may things to consider when deciding what type of server to use, do I build one or buy a used enterprise server, what type of processor and how many memory slots does the mother board have, how easy is it to upgrade the processor if I need more cores down the road, how much power does it use and how noisy is it. There seems to be endless things to consider and that’s because there is, and one thing I’ve learnt is that there is no one perfect server that will tick every box so it’s all about compromise.

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