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02:17, 16 August 2023 ‎PiB (hist | edit) ‎[253 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} IEC base2 notation for pebibytes. * PiB = pebibyte (2^50 / 1,125,899,906,842,624 bytes) See the following article for a fill list of IEC and SI data size notations: * IEC and SI Size Notations {{footer}}")
02:17, 16 August 2023 ‎TiB (hist | edit) ‎[247 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} IEC base2 notation for tebibytes. TiB = tebibyte (2^40 / 1,099,511,627,776 bytes) See the following article for a fill list of IEC and SI data size notations: * IEC and SI Size Notations {{footer}}")
02:16, 16 August 2023 ‎MiB (hist | edit) ‎[241 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} IEC base2 notation for mebibytes. * MiB = mebibyte (2^20 / 1,048,576 bytes) See the following article for a fill list of IEC and SI data size notations: * IEC and SI Size Notations {{footer}}")
02:16, 16 August 2023 ‎KiB (hist | edit) ‎[237 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} IEC base2 notation for kibibytes. * KiB = kibibyte (2^10 / 1,024 bytes) See the following article for a fill list of IEC and SI data size notations: * IEC and SI Size Notations {{footer}}")
02:15, 16 August 2023 ‎IEC and SI Size Notations (hist | edit) ‎[1,545 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} How data sizes are shortened varies depend on whether the program or author is using base2 and base10 notation. The short-form notation followed by it's English long-form name for each type is listed below. Then it shows in the braces the X to the power of Y value that it represents followed, finally, by the exact number of bytes represented. = base2 Notation = IEC Notation Size -------------- --------------------------------...")
02:14, 16 August 2023 ‎GiB (hist | edit) ‎[243 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} IEC base2 notation for gibibytes. GiB = gibibyte (2^30 / 1,073,741,824 bytes) See the following article for a fill list of IEC and SI data size notations: * IEC and SI Size Notations {{footer}}")
01:55, 16 August 2023 ‎TLUG Talk: Storage Technologies and Theory (hist | edit) ‎[50,364 bytes] ‎Digimer (talk | contribs) (Created page with "{{talk_header}} '''Note''': This talk is quite old, and much has happened in storage tech since this talk was given. This was the first IT-related public talk I gave and as such, it's not my favourite work. I present it here though for historical reasons. Take it all with a healthy grain a salt. '''''Storage Technologies and Theory''''' '''An AN!Speech to TLUG, May 2002''' = Introduction = Good day! I wanted to speak with you all today to help you make a more e...")
01:54, 16 August 2023 ‎Write-back (hist | edit) ‎[2,012 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Write-back caching is a technology used in disk storage to improve performance. It works by providing an amount of high-speed, volatile memory used to store data destined for non-volatile storage on relatively slow hard drives or solid state drives. Write-back caching is particularly useful on traditional platter-based hard drives and RAID arrays where highly random write access is expected. It allows for writes to be buffered, masking the performance lo...")
01:54, 16 August 2023 ‎IOPS (hist | edit) ‎[428 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto}} IOPS is an acronym for '''I'''nput/output '''O'''perations '''P'''er '''S'''econd. It is a measure of storage performance used to indicate how many read and how many write operations can be serviced, on average, per second. This measurement is particularly important for storage backing services with highly random reads and writes. To learn more: * [https://en.wikipedia.org/wiki/IOPS IOPS on Wikipedia] {{footer}}")
01:50, 16 August 2023 ‎Split-brain (hist | edit) ‎[2,778 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} {{warning|1=A "split-brain" condition is a potentially catastrophic event in clustering.}} It is a particular risk in two-node clusters, but can occur in larger clusters if quorum is not honoured. This section uses language specific to two node split-brain conditions, but "node" could be replaced with "partition" to describe a subsection of a cluster and still be accurate. A split-brain is a state in which two nodes lose contact with one another a...")
01:47, 16 August 2023 ‎Support (hist | edit) ‎[1,180 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} = Community Support = If you need help with an Anvil! cluster, Striker, ScanCore or other AN!Tutorials please use one of the options below. == Mailing List == Support for the Anvil! platform can be found on the [http://clusterlabs.org/wiki/Mailing_lists Cluster Labs] mailing list. * [http://clusterlabs.org/mailman/listinfo/users Clusterlabs - Users] mailing list. == IRC Channel == Support can also be found on the [https://libera.chat/ Libera chat] [...")
01:38, 16 August 2023 ‎Selecting Hardware For Your Anvil! (hist | edit) ‎[30,671 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} This guide's goal is to provide a high-level overview on how to match appropriate hardware for anticipated loads on your ''Anvil!'' platform. = System Requirements = To provide full stack redundancy, there are minimum system requirements. These are not performance requirements, but instead, minimum features and capabilities. = Foundation Pack = The foundation pack consists of redundant power...")
01:24, 16 August 2023 ‎Gluster (hist | edit) ‎[161 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} See: http://www.gluster.org/docs/index.php/GlusterFS See: http://www.gluster.org/ See: http://en.wikipedia.org/wiki/GlusterFS {{footer}}")
01:23, 16 August 2023 ‎DRBD (hist | edit) ‎[478 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} '''D'''istributed '''R'''eplicated '''B'''lock '''D'''evice, [https://linbit.com/drbd/ DRBD], is a software product created by [LINBIT https://linbit.com/]. It is, at it's simplest description, a program that insures data on two storage devices, on different hosts, are identical. It differs from programs like gluster and ceph in that it's core focus is resiliency over scalability. In this way, it is a perfect fit for the Anvil! cluster. {{footer}}")
23:54, 15 August 2023 ‎Generate 8bit dec to hex to bin chart.pl (hist | edit) ‎[1,380 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} A short script that generates a byte-length chart of decimal to hexadecimal to binary values. <source lang="perl"> #!/usr/bin/perl # Author: Madison Kelly; mkelly@alteeve.com # Date: Jun. 21, 2010 # License: GPLv2 # Be clean use strict; use warnings; # Headers print " Dec. | Hex. | Binary\n"; print "------+-------+-----------\n"; foreach my $dec (0..255) { # Convert the decimal to hexadecimal and pad the result with a lea...")
23:52, 15 August 2023 ‎Base-10 (hist | edit) ‎[246 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Base-10 is a counting system made up of ten digits, '0' through '9'. This is in contrast with the binary 'Base-2' counting system that uses only two digits, 0 and 1. Base-10 is used to represent decimal values. {{footer}}")
23:52, 15 August 2023 ‎Decimal (hist | edit) ‎[226 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} In computing terms, 'decimal' refers to the Base-10 Roman counting system that uses ten base digits (0 through 9) to represent numerical values. It is the "normal" counting system in most societies. {{footer}}")
23:51, 15 August 2023 ‎Hex (hist | edit) ‎[78 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} The term '''Hex''' is a short form of Hexadecimal. {{footer}}")
23:51, 15 August 2023 ‎ASCII (hist | edit) ‎[687 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} ASCII is an acronym for 'American Standard Code for Information Interchange'. See: http://en.wikipedia.org/wiki/ASCII Operating systems that follow the ASCII standard will always interpret the lower 7 bits of a byte to represent the same value. These seven bits cover 128 possible combinations. Of those, the first 32 (0-31) and last entry (127) are not printable character, but instead are "control characters". These are codes used to control certain...")
23:50, 15 August 2023 ‎Hexadecimal (hist | edit) ‎[8,623 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Hexadecimal is a method of representing 4 bits of data (known as a nibble) using a single ASCII character in the range from [0-9a-f]. = Use = Hexadecimal is very often used where a long binary string needs to presented to a human user. A good example would be the colour setting used on most modern graphics and web programs. Continuing this example, computer colours are often represented as six hexadecimal digits. Each pair, that is each byte, re...")
23:50, 15 August 2023 ‎Nibble (hist | edit) ‎[102 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A nibble is 4 bits and can be represented as single hexadecimal value. {{footer}}")
23:48, 15 August 2023 ‎Big Endian (hist | edit) ‎[534 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} In a binary string, 'Big Endianess' indicated that the least significant bit is on the right side. A big-endian byte would thus be structured like this: 0 0 0 0 0 0 0 0 <- Binary string consisting of 8-bits. | | | | | | | \- 128 | | | | | | \--- 64 | | | | | \----- 32 | | | | \------- 16 | | | | | | | \----------- 8 | | \------------- 4 | \--------------- 2 \----------------- 1 ^...")
23:47, 15 August 2023 ‎Endianess (hist | edit) ‎[336 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Endianess is the term used when describing the relative values of binary digits. There are two types; * Big Endian, where the least significant bit is the left-most value in the binary string. * Little Endian, where the least significant bit is the right-most value in the binary string. {{footer}}")
23:47, 15 August 2023 ‎LSB (hist | edit) ‎[135 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} 'LSB' is an acronym for 'Least Significant Bit' and is used to indicate 'Endianess' in a binary string. {{footer}}")
23:45, 15 August 2023 ‎Little Endian (hist | edit) ‎[561 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} In a binary string, 'Little Endianess' indicated that the least significant bit is on the left side of a binary string. A little-endian byte would thus be structured like this: 0 0 0 0 0 0 0 0 <- Binary string consisting of 8-bits. | | | | | | | \- 1 | | | | | | \--- 2 | | | | | \----- 4 | | | | \------- 8 | | | | | | | \----------- 16 | | \------------- 32 | \--------------- 64 \----------------- 128...")
23:45, 15 August 2023 ‎Base-2 (hist | edit) ‎[226 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Base-2 is a counting system made up of only two digits, '0' and '1'. This is in contrast with the Roman 'Base-10' counting system that uses 10 digits, 0-9. Base-2 is used to represent binary values. {{footer}}")
23:44, 15 August 2023 ‎Binary (hist | edit) ‎[2,662 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Binary is a form of counting that uses a base-2 system, a counting system with 2 digits. Binary uses only '0' and '1', which relates to an electrical 'low' (0) or 'high' (1) signal. This can conceptually be extended to 'false' (0) or 'true' (1). In computing, binary is used for all forms of calculations. Larger values are expressed as being 'X-bits', where 'X' is the number of 'BInary digiTs' used to create the value. Modern computers generally use multi...")
23:44, 15 August 2023 ‎Bits (hist | edit) ‎[128 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A 'Bit' is a single Base-2 'BInary DigiT'; 0 or 1. See 'Binary' for more information. {{footer}}")
23:43, 15 August 2023 ‎Byte (hist | edit) ‎[5,209 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A byte is the smallest unit of storage used in modern computers. It is made of 8 bits and can be arranged in 256 possible combinations. These possible combinations are used to represent a base set of values, the specifics of which depend on the operating system being used. Most modern operating systems conform to ASCII standards and thus share the same representative values for the first 128 possible combinations. In the example below, Little Endian...")
23:42, 15 August 2023 ‎Block (hist | edit) ‎[1,730 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A block is a collection of physical units of storage on a storage device or medium. A common 'block size' is 2,048 bytes, which could consist of 4x512byte sectors on a hard drive. A block is the smallest unit of space that a file system will use when storing data. If a file is smaller that this size, it will still use up the rest of the space. This of a block as a filing cabinet drawer with a set number of file folders (which actually...")
23:41, 15 August 2023 ‎SSD (hist | edit) ‎[408 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} '''SSD''' stands for 'Solid State Drive'. These are like traditional Hard Disk Drives but instead of using a rotating magnetic platter, they use a flash RAM device. This allows the drive to be much more tolerant of motion as there is no risk of centripetal forces causing the read head on a tradition hard drive from contacting the rotating platters. SSD uses no moving parts. {{footer}}")
23:40, 15 August 2023 ‎HDD (hist | edit) ‎[354 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A "hard drive", also known as a "fixed disk", "hard disk drive (HDD)", is a physical device, traditionally using rotating magnetic platters, to store data. Modern hard drives can instead use flash memory, though often these are called 'Solid State Drives', though they server the same function and use the same interfaces. {{footer}}")
23:40, 15 August 2023 ‎RAID (hist | edit) ‎[49,250 bytes] ‎Digimer (talk | contribs) (Created page with "{{fs_header}} Redundant Array of Inexpensive Disks. This is a collection of storage devices (traditionally platter-based hard drives) used together in one of 6 base "levels" to provide redundancy. RAID level 0 is not a true RAID level, but is often referenced and thus worth noting. It is not, however, redundant. * RAID0 - Striping only, NO redundancy (not a true RAID level) * RAID1 - Mirroring only. * RAID2 - Proprietary RAI...")
19:41, 15 August 2023 ‎Scancore (hist | edit) ‎[9,669 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} {{warning|1=This is little more that raw notes, do not consider anything here to be valid or accurate at this time.}} = ScanCore - The Decision Engine = ScanCore is, at its core, a "decision engine". It was created as a way for Anvil! systems to make intelligent decisions based on data coming in from any number of places. It generates alerts for admins, so in this regard it is an alert and monitoring solution, but that is almost a secondary benef...")
19:14, 15 August 2023 ‎Intelligent Availability (hist | edit) ‎[8,666 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} Intelligent Availability™ is the successor to High Availability. For a system to be defined as "IA", it must meet the following requirements and design focus; 1. Where HA is reactive, IA is proactive. 2. Complete stack redundancy with no single point of failure. 3. IA must survive both failure and recovery without interruption. 4. Over-provisioning/thin-provisioning is not allowed. 5. Performance must remain consistent in a degraded state. 6. Human in...")
19:12, 15 August 2023 ‎Anvil! (hist | edit) ‎[554 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} "'''Anvil!'''" is the name of the Intelligent Availability™ platform. The platform consists of; * A full-stack, zero single point of failure hardware architecture * The Striker web user interface; Designed simple to minimize potential for human error. * Scancore decision engine that proactively mitigates changing risks; ** Automated live-migration ** Autonomous Load shedding and recovery ** Autonomous Emergency shutdown and recovery * What...")
19:11, 15 August 2023 ‎UPS (hist | edit) ‎[461 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} thumb|right|500px|APC brand [http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SMT1500RM2U SMT1500RM2U] UPS. Photo by APC. A UPS, Uninterrupted Power Supply, is a device that uses batteries to provide line voltage to equipment when the power from building mains is lost. These are used extensively in server rooms, data centres and in Anvil! platforms. {{footer}}")
18:59, 15 August 2023 ‎Configuring an APC AP7900 (hist | edit) ‎[18,414 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} thumb|right|400px|APC [http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=AP7900 AP7900 8-Outlet 1U] 120vAC PDU. Photo by [http://www.apcmedia.com/prod_image_library/index.cfm?search_item=AP7900# APC]. = Purpose of This Tutorial = The APC-brand '''AP7900''' (and '''AP7900B''') switched PDU is an excellent backup fence device. All ''Anvil!'' systems we build use a pair of th...")
18:51, 15 August 2023 ‎PDU (hist | edit) ‎[680 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} thumb|right|400px|APC [http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=AP7900 AP7900 8-Outlet 1U] 120vAC PDU. Photo by [http://www.apcmedia.com/prod_image_library/index.cfm?search_item=AP7900# APC]. In clustering, an addressable '''PDU''' ('''P'''ower '''D'''istribution '''U'''nit) is, essentially, a network-connected power bar where the power to any given plug can be remotely and individually con...")
18:49, 15 August 2023 ‎PSU (hist | edit) ‎[406 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A '''P'''ower '''S'''upply '''U'''nit, or "PSU", is the device that converts mains power into the various voltages needed inside of a computer, switch or other electronic device. In Anvil! clusters, most devices have redundant power supplies. This allows a device to be powered by two different power sources so that the loss of one power rail doesn't cause the device to shut down. {{footer}}")
18:44, 15 August 2023 ‎BMC (hist | edit) ‎[298 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} '''BMC''' is an acronym for "Baseboard Management Card", which is the physical circuit board to provides IPMI functionality to a server. Learn more: * [http://en.wikipedia.org/wiki/Baseboard_management_controller#Baseboard_management_controller BMC] on Wikipedia. {{footer}}")
18:09, 15 August 2023 ‎OEM (hist | edit) ‎[171 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} OEM is an acronym for '''O'''riginal '''E'''quipment '''M'''anufacturer. It generally refers to the company that built a physical device or widget. {{footer}}")
18:06, 15 August 2023 ‎SAN (hist | edit) ‎[396 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} SAN is an acronym for '''''S'''torage '''A'''rea '''N'''etwork''. It differs from NAS in that it makes it's disk space available to multiple servers at the block level. It generally uses many disk drives in an array using high-speed copper or fiber networking technologies and is generally fault tolerant. See: http://en.wikipedia.org/wiki/Storage_area_network {{footer}}")
18:06, 15 August 2023 ‎Fencing (hist | edit) ‎[1,694 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} In clustering, '''fence''' (also called 'stonith') refers to the action of removing a node from the cluster. A fence is carried out when the cluster software determines a node is faulty. Once this decision is made, the cluster software consults it's configuration for information on how to carry out the fence. The fence action is in turn carried out by a software or hardware action. The details of which depend on the fence method(s) configured for the node be...")
18:05, 15 August 2023 ‎Quorum (hist | edit) ‎[1,804 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} In clustering terms, '''quorum''' is synonymous with "majority". All nodes and quorum disks, when used, are assigned a number of votes. The cluster is then told how many votes to expect (the sum of all nodes plus the quorum disk). When a problem occurs that caused the cluster to split into two or more partitions, each partition will add up the votes of itself plus the devices it can talk to. If the resulting count is greater than half, that partition is deter...")
18:04, 15 August 2023 ‎The 2-Node Myth (hist | edit) ‎[8,242 bytes] ‎Digimer (talk | contribs) (Created page with "{{header}} A common argument in the availability world is "You need at least 3-nodes for availability clustering". This article aims to disprove that. To understand this argument we must first discuss two concepts in availability clustering; Quorum and fencing (also called 'stonith'). = Quorum = "Quorum" is a term used to define simple majority. Nodes in a cluster have a default value of '1'. Said mathematically, quorum is > 50%. When a cluster is quora...")
23:46, 11 August 2023 ‎How To (hist | edit) ‎[51 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} How-to articles; * {{footer}}")
21:16, 11 August 2023 ‎IPMI (hist | edit) ‎[27,359 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} IPMI is an acronym for '''I'''ntelligent '''P'''latform '''M'''anagement '''I'''nterface. This is a technology built into many server-grade mainboards. This is called the '''B'''aseboard '''M'''anagement '''C'''ontroller, or '''BMC'''. IPMI, via the BMC, allows "out of band" access to a server. This means that, via an IPMI interface, a user can remotely connect to a server regardless of it's power state and sensor data. The BMC is isolated from the hos...")
01:42, 4 August 2023 ‎Anvil! Networking (hist | edit) ‎[16,350 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} The Anvil! Cluster implements four main network types, each of which there could be one or more of. {| class="wikitable" !style="white-space:nowrap; text-align:center;"|Network Name !style="white-space:nowrap; text-align:center;"|Prefix !style="white-space:nowrap; text-align:center;"|Subnet !style="white-space:nowrap; text-align:center;"|Used By !style="white-space:nowrap; text-align:center;"|Description |- !style="white-space:nowrap; text-align:l...")
03:07, 27 July 2023 ‎Configuring Networking in RHEL9 (hist | edit) ‎[1,412 bytes] ‎Digimer (talk | contribs) (Created page with "{{howto_header}} This tutorial covers a few different network configurations. This should be generally useful, but it is written with the Anvil! cluster member machine. Striker dashboards generally had two interfaces, directly configured. Anvil! nodes consist of two sub-nodes, acting in unison. Those sub-nodes have 8 interfaces, paired into four bonds. Two of those bonds will have IPs directly, and two will have bridge interfaces. DR hosts often match the hardwa...")

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