Ceph crush map. 2 class ssd # types type 0 osd type 1 host type 2 chassis Nov 21, 2013 · A new datacenter is added to the crush map of a Ceph cluster: # ceph osd crush add-bucket fsf datacenter added bucket fsf type datacenter to crush map. All CRUSH changes that are necessary for the overwhelming majority of installations are possible via the standard ceph CLI and do not require manual CRUSH map edits. The purpose of creating a bucket hierarchy is to segregate the leaf nodes by their failure domains, such as hosts, chassis, racks, power distribution units, pods, rows, rooms, and data By using an algorithmically-determined method of storing and retrieving data, Ceph avoids a single point of failure, a performance bottleneck, and a physical limit to its scalability. crushtool is a utility that lets you create, compile, decompile and test CRUSH map files. Previously, any non-trivial data placement policy required manual editing of the CRUSH map, either to adjust the hierarchy or to write the rules that Aug 12, 2021 · This article will walk through how to add “hba” and “port” buckets to an existing CRUSH map. To view a CRUSH map, execute ceph osd getcrushmap-o {filename}; then, decompile it by executing crushtool-d {comp-crushmap-filename}-o {decomp-crushmap-filename}. However, there are times when you may choose to edit it, such as changing the default bucket types, or using a bucket algorithm other than straw. CRUSH is implemented as a pseudo-random, deterministic function that maps an input value, typically an object or ob- The CRUSH Map: Contains a list of storage devices, the failure domain hierarchy (for example, device, host, rack, row, room), and rules for traversing the hierarchy when storing data. CRUSH uses a map of the cluster (the CRUSH map) to map data to OSDs, distributing the data across the cluster in accordance with configured replication policy and Ceph Clients and Ceph OSDs both use the CRUSH map and the CRUSH algorithm. 2 device 3 osd. To remove the OSD from the CRUSH map hierarchy, run the following command: Sep 26, 2017 · The flexibility of the CRUSH map in controlling data placement in Ceph is one of the system's great strengths. 4 CRUSH Map and Rule. 3 device 4 osd. By reflecting the underlying physical organization of the installation, CRUSH can model—and thereby address—potential sources of はじめに. Ceph Clients: By distributing CRUSH maps to Ceph clients, CRUSH empowers Ceph clients to communicate with OSDs directly. Previously, any non-trivial data placement policy required manual editing of the CRUSH map, either to adjust the hierarchy or to write the rules that Jan 16, 2014 · $ ceph osd getcrushmap -o crushmap_optimal. The purpose of creating a bucket hierarchy is to segregate the leaf nodes by their failure domains, such as hosts, chassis, racks, power distribution units, pods, rows, rooms, and data To map placement groups to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types (i. 1 class ssd device 2 osd. Set the CRUSH map, as described in Setting a CRUSH map. 5. 6 The utils-checkPGs. To map placement groups to OSDs, a CRUSH map defines a hierarchical list of bucket types. The CRUSH map contains at least one hierarchy of nodes and leaves. If you would like to remove all the host’s OSDs as well, please start by using the ceph orch host drain command to do so. 2 class hdd # types type 0 osd type 1 host type 2 chassis Description . This erasure-code profile is equivalent to a replicated pool of size three, but with different storage requirements: instead of requiring 3TB to store 1TB, it requires only 2TB to store 1TB. OSD_ORPHAN An OSD is referenced in the CRUSH map hierarchy, but does not exist. The purpose of creating a bucket hierarchy is to segregate the leaf nodes by their failure domains, such as hosts, chassis, racks, power distribution units, pods, rows, rooms, and data Ceph’s deployment tools generate a default CRUSH map that lists devices from the OSDs you defined in your Ceph configuration file, and it declares a bucket for each host you specified in the [osd] sections of your Ceph configuration file. CRUSH is a pseudo-random data distribution algorithm that efficiently maps input values (which, in the context of Ceph, correspond to Placement Groups) across a heterogeneous, hierarchically structured device map. After modifying a crush map it should be tested to check that all rules can ~# ceph osd getcrushmap -o /tmp/crushmap ~# crushtool -d /tmp/crushmap -o crush_map ~# vi crush_map This is what my crush map's devices section looked like before: # devices device 0 osd. txt # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 1 This is a wrapper around osdmaptool (8), relying on its –test-map-pgs-dump option to get the list of changed pgs. Ceph is an open source distributed storage system designed to evolve with data. For details, see Add/Move an OSD. txt -o . 描述 控制当 OSD 在 CRUSH map 中标记为 down 时，使用替换策略 CRUSH。如果此规则要与复制池一起使用，则应首先 将它用于 纠删代码池，如果用于纠删代码池，则应 耗尽。 CRUSH Maps . You should create your own CRUSH maps with buckets that reflect your cluster’s failure domains to To map placement groups to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types (i. Crimson A next-generation OSD architecture whose main aim is the reduction of latency costs incurred due to cross-core By using an algorithmically-determined method of storing and retrieving data, Ceph avoids a single point of failure, a performance bottleneck, and a physical limit to its scalability. That enables the client to connect directly to the OSD, access the placement group and read or write object data. The CRUSH Map: Contains a list of storage devices, the failure domain hierarchy (for example, device, host, rack, row, room), and rules for traversing the hierarchy when storing data. 提取最新的 CRUSH map： ceph osd getcrushmap -o /tmp/crush; 调整可调项。这些值显示为为我们测试的大型集群和小集群提供最佳行为。此外，您需要额外指定 --enable-unsafe-tunables 参数到 crushtool 才能正常工作。请谨慎使用这个选项： CRUSH maps contain a list of OSDs, a list of ‘buckets’ for aggregating the devices into physical locations, and a list of rules that tell CRUSH how it should replicate data in a Ceph cluster’s pools. To activate a CRUSH Map rule for a specific pool, identify the common rule number and specify that rule number for the pool when creating the pool. Removal from the CRUSH map will fail if there are OSDs deployed on the host. As you can see racks are empty (and this normal): ```bash $ ceph osd tree The CRUSH Map: Contains a list of storage devices, the failure domain hierarchy (for example, device, host, rack, row, room), and rules for traversing the hierarchy when storing data. We can query the CRUSH map directly from the ceph osd commands. 4 device 5 osd. CRUSH hierarchy The CRUSH map is a directed acyclic graph, so it can accommodate multiple hierarchies, for example, performance domains. CRUSH allows Ceph clients to communicate with OSDs directly rather than through a centralized server or broker. It is also one of the most painful and awkward parts of the cluster to manage. It pseudo-randomly maps data to OSDs, distributing the information across the cluster by following a configured replication policy and failure domain. , under #types in the generated CRUSH map). Additionally it uses pg stats to calculate the numbers of objects and bytes moved. crush_location = root=default row=a rack=a2 chassis=a2a host=a2a1. bin # 将新生成的二进制形式的 CRUSH map 导入至集群中 $ ceph osd crush rule ls replicated_rule myerasurepool crush_test_replicated # 查看当前集群最新版本的 CRUSH 规则 Sep 26, 2017 · The flexibility of the CRUSH map in controlling data placement in Ceph is one of the system's great strengths. By reflecting the underlying physical organization of the installation, CRUSH can model—and thereby address—potential sources of CRUSH Maps . See the “Cluster Map” section of the Architecture document for details. Note that this mode is fully backward compatible with older clients: when an OSD Map and CRUSH map are shared with older clients, Ceph presents the optimized weights as the “real” weights. By reflecting the underlying physical organization of the Ceph Storage Cluster, CRUSH can model, and thereby This is a wrapper around osdmaptool (8), relying on its --test-map-pgs-dump option to get the list of changed pgs. 8 device 9 osd. To edit an existing CRUSH map: To map placement groups (PGs) to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types under #types in the generated CRUSH map. The purpose of creating a bucket hierarchy is to segregate the leaf nodes according to their failure domains (for example: hosts, chassis, racks, power distribution units, pods, rows Add the OSD to the CRUSH map so that the OSD can begin receiving data. CRUSH failure domain Having multiple object replicas or M erasure coding chunks helps prevent data loss, but it is not sufficient to address high availability. Description . The purpose of creating a bucket hierarchy is to segregate the leaf nodes according to their failure domains (for example: hosts, chassis, racks, power distribution units, pods, rows Description . When this option has been added, every time the OSD starts it verifies that it is in the correct location in the CRUSH map and moves itself if it is not. CRUSH Map 里的第二个列表定义了 bucket （桶）类型，桶简化了节点和叶子层次。节点（或非叶子）桶在分级结构里一般表示物理位置， 节点汇聚了其它节点或叶子，叶桶表示 ceph-osd 守护进程及其对应的存储媒体。 Feb 2, 2015 · # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 0 tunable chooseleaf_vary_r 0 # devices device 0 osd. After modifying a crush map it should be tested to check that all rules can crushdiff -- ceph crush map test tool; crushtool -- CRUSH map manipulation tool; librados-config -- display information about librados; monmaptool -- ceph monitor cluster map manipulation tool; osdmaptool -- ceph osd cluster map manipulation tool; rados -- rados object storage utility; ceph-post-file -- post files for ceph developers Notably, this mode is fully backwards compatible with older clients: when an OSDMap and CRUSH map is shared with older clients, we present the optimized weights as the “real” weights. 2 crushtool CLI. By using an algorithmically-determined method of storing and retrieving data, Ceph avoids a single point of failure, a performance bottleneck, and a physical limit to its scalability. osdmaptool is a utility that lets you create, view, and manipulate OSD cluster maps from the Ceph distributed storage system. Note. Feb 2, 2015 · # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 0 tunable chooseleaf_vary_r 0 # devices device 0 osd. CRUSH maps contain a list of OSDs, a list of ‘buckets’ for aggregating the devices into physical locations, and a list of rules that tell CRUSH how it should replicate data in a Ceph cluster’s pools. Learn how CRUSH maps compute storage locations and distribute data across the cluster in accordance with replication policy and failure domains. bin -o crushmap_optimal. Ceph supports petabyte-scale data storage clusters, with storage pools and placement groups that distribute data across the cluster using Ceph’s CRUSH algorithm. 8 Data Movement. The algorithm was originally described in detail in the following paper (although it has evolved some since then): Jan 9, 2023 · The crush map is a map of the cluster. 7 device 8 osd. ), and rules for traversing the hierarchy when storing data. CRUSH Maps . I don't know how to do this sort of thing, but I'm sure there are tools that could be used to translate a crush map into a visual representation of a tree of bubbles of some kind. The CRUSH map for your storage cluster describes your device locations within CRUSH hierarchies and a rule for each hierarchy that determines how Ceph stores data. If you specify at least one bucket, the command will place the OSD into the most specific bucket you specify, and it will move that bucket underneath any other buckets you specify. Create a new CRUSH rule that uses both racks; Let's start by creating two new racks: bash $ ceph osd crush add-bucket rack1 rack added bucket rack1 type rack to crush map $ ceph osd crush add-bucket rack2 rack added bucket rack2 type rack to crush map. 4. 6 device 7 osd. Options --print Generally, modifying your CRUSH map at runtime with the Ceph CLI is more convenient than editing the CRUSH map manually. , device, host, rack, row, room, etc. 1 class hdd device 2 osd. 因此，Ceph 管理员可以在单个 CRUSH map 中支持包含多个根节点的多个层次结构。 例如，管理员可以创建表示较高成本 SSD 的层次结构，以获得高性能，并使用 SSD 日志创建成本更低的硬盘驱动器，以获得中等性能。 CRUSH Maps . To get the CRUSH map for your cluster, run a command of the following form:. CRUSH map 是环形图，因此它可以容纳多个层次结构，如性能域。创建和修改 CRUSH 层次结构的最简单方式是使用 Ceph CLI，但您也可以编译 CRUSH map、对其进行编辑、重新编译并激活它。 By using an algorithmically-determined method of storing and retrieving data, Ceph avoids a single point of failure, a performance bottleneck, and a physical limit to its scalability. bin got crush map from osdmap epoch 186 $ crushtool -d crushmap_optimal. This is To map placement groups to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types (i. Note that there is another way to add a new OSD to the CRUSH map: decompile the CRUSH map, add the OSD to the device list, add the host as a bucket (if it is not already in the CRUSH map), add the device as an item in the host, assign the device a weight, recompile the CRUSH map, and set the CRUSH map. 9 device 10 # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 1 tunable chooseleaf_vary_r 1 tunable chooseleaf_stable 1 tunable straw_calc_version 1 tunable allowed_bucket_algs 54 # devices device 0 osd. To view a CRUSH map, run ceph osd getcrushmap-o {filename} and then decompile it by running crushtool-d {comp-crushmap-filename}-o {decomp-crushmap-filename}. The primary limitation of this mode is that the balancer cannot handle multiple CRUSH hierarchies with different placement rules if the subtrees of the Ceph is designed with the expectation that all parts of its network and cluster will be reliable and that failures will be distributed randomly across the CRUSH map. 1. 1 ceph CLI. It can also simulate the upmap balancer mode so you can get a sense of what is needed to balance your PGs. CRUSH maps use a hierarchy of devices, buckets, and rules to model the physical topology and data placement policy of Ceph clusters. The purpose of creating a bucket hierarchy is to segregate the leaf nodes according to their failure domains (for example: hosts, chassis, racks, power distribution units, pods, rows To map placement groups (PGs) to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types under #types in the generated CRUSH map. CRUSH uses a map of the cluster (the CRUSH map) to map data to OSDs, distributing the data across the cluster in accordance with configured replication policy and May 11, 2019 · Compile and inject the new CRUSH map in the Ceph cluster: crushtool -c crushmapdump-decompiled -o crushmapdump-compiled ceph osd setcrushmap -i crushmapdump-compiled. The purpose of creating a bucket hierarchy is to segregate the leaf nodes according to their failure domains (for example: hosts, chassis, racks, power distribution units, pods, rows 当您创建一个配置文件并使用Ceph -deploy部署Ceph时，Ceph将生成一个默认的map。默认的CRUSH map 是工作的。然而，当您部署大型数据集群时，您应该考虑开发一个定制CRUSH map，因为它将帮助您管理Ceph集群，提高性能并确保数据安全。 CRUSH map可以帮助你更快地识别错误。 Aug 9, 2024 · 1. For example in the GUI under Node -> Ceph -> Configuration on the right side. 结合实际的ceph环境，讲解CRUSH map中配置项的含义和 The CRUSH location for an OSD can be set by adding the crush_location option in ceph. The crush map describes where, what type Data Placement. e. The hierarchical layout describes the physical topology of the Ceph cluster. The bubbles could be annotated with extra info like weight, crush algorithm and hash type, and Erasure-code profiles . Checking the CRUSH map. txt # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 1 Ceph is an open source distributed storage system designed to evolve with data. 5 Configure the Failure Domain in CRUSH Map. To map placement groups (PGs) to OSDs across failure domains, a CRUSH map defines a hierarchical list of bucket types under #types in the generated CRUSH map. These CRUSH buckets then can be used as failure domains in a CRUSH rule. txt $ head -n6 crushmap_optimal. g. The CRUSH map for your storage cluster describes your device locations within CRUSH hierarchies and a ruleset for each hierarchy that determines how Ceph will store data. 7 I changed it to this - note I had to renumber The language used in crush maps is very well defined and hierarchical. /cm-firstn-1. 0 device 1 osd. and test CRUSH map files. 2 CRUSH Map 之桶类型. The primary restriction of this mode is that the balancer cannot handle multiple CRUSH hierarchies with different placement rules if the subtrees of the Aug 1, 2022 · We look into how to set up a good Crush Map and handle the placement and device types of your OSDs in your clusters. The CRUSH algorithm determines how to store and retrieve data by computing storage locations. Notably, it lets you extract the embedded CRUSH map or import a new CRUSH map. 3 device 4 device4 device 5 osd. 1 Overview ¶ The CRUSH Map in a Ceph cluster is best visualized as an inverted tree. 9 device 10 We have developed CRUSH (Controlled Replication Un-der Scalable Hashing), a pseudo-random data distribution algorithm that efficiently and robustly distributes object replicas across a heterogeneous, structured storage cluster. 01)で最新であるceph(octopus)の構築を目的としています。 また、自分で構築した手順の備忘録を兼ねているので、細かいところで間違いなどあるかもしれません。 osdmaptool is a utility that lets you create, view, and manipulate OSD cluster maps from the Ceph distributed storage system. conf, example:. py Script. Once you have your cluster up and running, you may begin working with data placement. Explore the art of writing and freely express yourself on Zhihu, a platform for sharing knowledge and insights. 5 device 6 osd. Check the OSD tree view 可预测性：通过对指定的CRUSH map进行离线计算即可预测出PG的分布情形，且与集群内实际使用完全一致; 虽然CRUSH算法为Ceph数据定位提供了有力的技术支持，但也依然存在一些缺陷，如： 假失败：因为计算的独立性CRUSH很难处理权重失衡（weight skew）的情形。 The set of maps consisting of the monitor map, OSD map, PG map, MDS map, and CRUSH map, which together report the state of the Ceph cluster. Options --print crushtool is a utility that lets you create, compile, decompile and test CRUSH map files. Contribute to 0voice/kernel_awsome_feature development by creating an account on GitHub. Because the CRUSH map is in a compiled form, you must first decompile it before you can edit it. Manually editing the CRUSH map is considered an advanced administrator operation. crushtool is a utility that lets you create, compile, decompile. e. この記事では、タイトルのとおり現時点(2021. ceph osd crush move fsf root=default. ceph osd tree id weight type name up/down reweight Sep 7, 2022 · CRUSH map是ceph集群物理拓扑的抽象，CRUSH算法通过CRUSH map中的ceph集群拓扑结构、副本策略以及故障域等信息，将数据伪随机地分布到集群的各个OSD上。 因此，读懂CRUSH map也有助于我们理解CRUSH算法。 CRUSH map含义. The default erasure-code profile can sustain the overlapping loss of two OSDs without losing data. CRUSH is a pseudo-random data distribution algorithm that efficiently maps input values (typically data objects) across a heterogeneous, hierarchically structured device map. 0 class hdd device 1 osd. CRUSH Maps¶ The CRUSH algorithm determines how to store and retrieve data by computing data storage locations. CRUSH uses a map of the cluster (the CRUSH map) to map data to OSDs, distributing the data across the cluster in accordance with configured replication policy and OSD_<crush type>_DOWN (for example, OSD_HOST_DOWN, OSD_ROOT_DOWN) All of the OSDs within a particular CRUSH subtree are marked “down” (for example, all OSDs on a host). Even if a switch goes down and causes the loss of many OSDs, Ceph is designed so that the remaining OSDs and monitors will route around such a loss. prompt:: bash $ ceph osd getcrushmap -o {compiled-crushmap-filename} Ceph outputs (-o) a compiled CRUSH map to the filename that you have specified. To modify this crush map, first extract the crush map: $ sudo ceph osd Jul 19, 2020 · 3. This means that Ceph clients avoid a centralized object look-up table that could act as a single point of failure, a performance bottleneck, a connection limitation at a centralized look-up server and a physical limit to the storage cluster’s scalability. Jun 20, 2020 · You will also see a bucket in the CRUSH Map for the node itself. . The CRUSH map command-line utility can save a lot of the system administrator's time as compared to the conventional way of viewing and editing it after the decompilation of the CRUSH map: To view the CRUSH map, execute the following command: # ceph osd The CRUSH Map: Contains a list of storage devices, the failure domain hierarchy (e. # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 1 tunable chooseleaf_vary_r 1 tunable chooseleaf_stable 1 tunable straw_calc_version 1 tunable allowed_bucket_algs 54 # devices device 0 osd. This is a wrapper around osdmaptool (8), relying on its --test-map-pgs-dump option to get the list of changed pgs. By default, the crush map tells Ceph to replicate the PGs into different hosts. moved item id -13 name 'fsf' to location {root=default} in crush map. The primary limitation of this mode is that the balancer cannot handle multiple CRUSH hierarchies with different placement rules if the subtrees of the Because each pool might map to a different CRUSH rule, and each rule might distribute data across different devices, Ceph will consider the utilization of each subtree of the hierarchy independently. CRUSH empowers Ceph clients to communicate with OSDs directly rather than through a centralized server or broker. Once the OSDs have been removed, then you may direct cephadm remove the CRUSH bucket along with the host using the --rm-crush-entry flag. The ceph osd crush add command allows you to add OSDs to the CRUSH hierarchy wherever you wish. 深入研究 kvm,ceph,fuse特性，包含开源项目，代码案例，文章，视频，架构脑图等. As Ceph processes the CRUSH rule, it identifies the primary OSD that contains the placement group for an object. For example, a pool that maps to OSDs of class ssd and a pool that maps to OSDs of class hdd will each have optimal PG counts that are determined Jan 16, 2014 · $ ceph osd getcrushmap -o crushmap_optimal. g You want to create a ceph storage pool that will distribute objects or objects chunks across OSDs grouped by the HBA or card they attached to rather than at the host level. 7 Ceph Deployments. bin # 将文本形式的 CRUSH map 编译为二进制形式 $ ceph osd setcrushmap -i . CRUSH Maps¶. CRUSH 规则定义 Ceph 客户端如何选择 bucket 以及其中的 Primary OSD 来存储对象，以及主要 OSD 选择存储桶和次要 OSD 以存储副本或编码区块的方式。 例如，您可以创建一个规则，为两个对象副本选择由 SSD 支持的一对目标 OSD，以及另一规则为三个副本选择由 SAS 驱动器 Dec 2, 2013 · $ crushtool -c . 1 device 2 osd. 0 device 1 device1 device 2 osd. CRUSH uses a map of the cluster (the CRUSH map) to map data to OSDs, distributing the data across the cluster in accordance with configured replication policy and crushtool is a utility that lets you create, compile, decompile and test CRUSH map files. The CRUSH algorithm computes storage locations in order to determine how to store and retrieve data. 0 class ssd device 1 osd. The list of bucket types are CRUSH Maps . Once all the OSDs that used to be in the node are gone, you can remove the node bucket with ( Ceph documentation ). CRUSH uses a map of the cluster (the CRUSH map) to map data to OSDs, distributing the data across the cluster in accordance with configured replication policy and Nov 27, 2018 · Ceph实践之Crushmap相关 初识crushmap. CRUSH Map 包含 OSD 列表、“桶”类型、把设备汇聚为物理位置的“桶”列表、和指示 CRUSH 如何复制存储池里的数据的规则列表。 Add the OSD to the CRUSH map so that the OSD can begin receiving data. ofwh uhr cdtqj cqn omnkwr hzsr suozbx bptvtc xoxnny jzgw