User contributions for Digimer
Jump to navigation
Jump to search
- 23:50, 15 August 2023 diff hist +102 N Nibble Created page with "{{header}} A nibble is 4 bits and can be represented as single hexadecimal value. {{footer}}" current
- 23:48, 15 August 2023 diff hist +534 N Big Endian 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 ^..." current
- 23:47, 15 August 2023 diff hist +336 N Endianess 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}}" current
- 23:47, 15 August 2023 diff hist +135 N LSB Created page with "{{header}} 'LSB' is an acronym for 'Least Significant Bit' and is used to indicate 'Endianess' in a binary string. {{footer}}" current
- 23:45, 15 August 2023 diff hist +561 N Little Endian 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..." current
- 23:45, 15 August 2023 diff hist +226 N Base-2 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}}" current
- 23:44, 15 August 2023 diff hist +2,662 N Binary 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..." current
- 23:44, 15 August 2023 diff hist +128 N Bits Created page with "{{header}} A 'Bit' is a single Base-2 'BInary DigiT'; 0 or 1. See 'Binary' for more information. {{footer}}" current
- 23:43, 15 August 2023 diff hist +5,209 N Byte 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..." current
- 23:42, 15 August 2023 diff hist +1,730 N Block 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..." current
- 23:41, 15 August 2023 diff hist +408 N SSD 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}}" current
- 23:40, 15 August 2023 diff hist +354 N HDD 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}}" current
- 23:40, 15 August 2023 diff hist −3 RAID
- 23:40, 15 August 2023 diff hist +885 N RAID 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..."
- 19:50, 15 August 2023 diff hist +24 Main Page →Tutorials
- 19:41, 15 August 2023 diff hist 0 Scancore
- 19:41, 15 August 2023 diff hist +28,140 N Scancore 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..."
- 19:40, 15 August 2023 diff hist +22 N ScanCore Redirected page to Scancore current Tag: New redirect
- 19:15, 15 August 2023 diff hist +43 Main Page →Tutorials
- 19:14, 15 August 2023 diff hist +8,666 N Intelligent Availability 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..." current
- 19:12, 15 August 2023 diff hist +554 N Anvil! 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..." current
- 19:11, 15 August 2023 diff hist +461 N UPS 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}}" current
- 19:10, 15 August 2023 diff hist +141 N File:Apc smt1500rm2u.jpg APC brand [http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SMT1500RM2U SMT1500RM2U] UPS. Photo by APC. current
- 19:07, 15 August 2023 diff hist +1,480 Build an M3 Anvil! Cluster →Adding Fence Devices
- 19:06, 15 August 2023 diff hist −1 PDUs Redirected page to PDU current Tag: New redirect
- 19:06, 15 August 2023 diff hist +18 N PDUs Created page with "#!REDIRECT PDU"
- 19:05, 15 August 2023 diff hist −3 Configuring an APC AP7900 →Serial Access current
- 19:03, 15 August 2023 diff hist +39 N Configuring an APC AP7900B Redirected page to Configuring an APC AP7900 current Tag: New redirect
- 19:03, 15 August 2023 diff hist +39 N APC AP7900 Redirected page to Configuring an APC AP7900 current Tag: New redirect
- 19:02, 15 August 2023 diff hist −17,962 APC AP7900B Redirected page to Configuring an APC AP7900 current Tag: New redirect
- 18:59, 15 August 2023 diff hist +18,417 N Configuring an APC AP7900 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..."
- 18:52, 15 August 2023 diff hist +19 N Fence device Redirected page to Fence current Tag: New redirect
- 18:51, 15 August 2023 diff hist +680 N PDU 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..." current
- 18:49, 15 August 2023 diff hist +406 N PSU 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}}" current
- 18:44, 15 August 2023 diff hist +298 N BMC 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}}" current
- 18:15, 15 August 2023 diff hist +19 Fencing →Power Fencing current
- 18:09, 15 August 2023 diff hist +171 N OEM 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}}" current
- 18:08, 15 August 2023 diff hist +21 N Fence Redirected page to Fencing current Tag: New redirect
- 18:07, 15 August 2023 diff hist +19 N Stonith Redirected page to Fence current Tag: New redirect
- 18:06, 15 August 2023 diff hist +396 N SAN 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<br /> {{footer}}" current
- 18:06, 15 August 2023 diff hist +1,675 N Fencing 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..."
- 18:06, 15 August 2023 diff hist +18 Quorum current
- 18:05, 15 August 2023 diff hist +1,786 N Quorum 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..."
- 18:05, 15 August 2023 diff hist +117 N Template:Header Created page with "{| style="border: 1px solid #f7f7f7; width: 100%;" cellpadding=1 | Main Page :: '''''{{PAGENAME}}''''' |}" current
- 18:04, 15 August 2023 diff hist +8,242 N The 2-Node Myth 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..." current
- 18:03, 15 August 2023 diff hist +120 Build an M3 Anvil! Cluster →Configuring the First Node
- 20:37, 14 August 2023 diff hist +137 Build an M3 Anvil! Cluster
- 23:46, 11 August 2023 diff hist +51 N How To Created page with "{{howto_header}} How-to articles; * {{footer}}" current
- 22:55, 11 August 2023 diff hist 0 IPMI →Testing the IPMI Connection From the Peer current
- 22:54, 11 August 2023 diff hist +3,549 IPMI
![thumb|right|500px|APC brand [http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SMT1500RM2U SMT1500RM2U] UPS. Photo by APC.](/index.php?title=File:Apc_smt1500rm2u.jpg){kind=link}
![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].](/index.php?title=File:APC_AP7900_Front-Right.jpg){kind=link}