Ceph osd reweight example. This tool primarily just addresses that deficiency.

Ceph osd reweight example Ceph’s data placement introduces a layer of indirection to ensure that data doesn’t bind directly to particular OSD addresses. Monitor deployment also sets important criteria for the entire cluster, such as the number of replicas for pools, the number of placement groups per OSD, the Surviving ceph-osd daemons will report to the monitors that the OSD appears to be down, and a new status will be visible in the output of the ceph health command, as in the following example: For example, NVMe or SSD devices. conf file. ceph osd reweight-by-utilization 120 (as an example) ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … The CRUSH location for an OSD can be set by adding the crush_location option in ceph. To encrypt your data, for security purposes, from the Features section of the form, select Encryption. I've had this happen, and it was an OSD imbalance. 58557 root default Executing this or other weight commands that assign a weight will override the weight assigned by this command (for example, osd reweight-by-utilization, osd crush weight, osd weight, in or out). 3 1 -7 4 rack rack1 -3 2 host host2 4 1 osd. Each leaf of the hierarchy consists Use Cases:Ceph provides massive storage capacity, and it supports numerous use cases. Object Storage Daemon (OSD) configuration options Understand the various Ceph Object Storage Daemon (OSD) configuration options that can be set during deployment. -K. <id>, as well as optional base64 cepx key for dm-crypt lockbox access and a dm-crypt key. Advanced Cluster Configuration These examples show how to perform advanced configuration tasks on your Rook storage cluster. 49709 0. adjust weight downward on OSD s that are over 120% utilized). Sep 26, 2017 · $ ceph osd crush class ls [ "hdd", "ssd" ] You can list OSDs that belong to a class: $ ceph osd crush class ls-osd ssd 0 1 You can also rename classes, which safely updates all related elements: the OSD device class properties and the CRUSH rules are updated safely in unison, with the " ceph osd crush class rename " command. For example, rows, racks, chassis, hosts, and devices. A quick way to use the Ceph client suite is from a Rook Set CRUSH weights in terabytes with a CRUSH map. DB devices are used to store BlueStore’s internal metadata and are used only if the DB device is faster than the primary device. Executing this or other weight commands that assign a weight will override the weight assigned by this command (for example, osd reweight-by-utilization, osd crush weight, osd weight, in or out). Since this is not always practical, you may incorporate devices of different size and use a relative weight so that Ceph will distribute more data to larger drives and less data to smaller drives. 5 to the 256GB drive. If a Ceph OSD is in an up state, it can be either in the storage cluster, where data can be read and written, or it is out of the storage cluster. 2-11 all ceph-nodes showing us the same like Adding/Removing OSDs ¶ When you have a cluster up and running, you may add OSDs or remove OSDs from the cluster at runtime. A notification displays that the OSD was created successfully and the OSD status changes from in and down to in and up. The weight value is in the range 0 to 1, and the command forces CRUSH to relocate a certain amount (1 - weight) of the data that would otherwise be on this OSD. $ ceph osd tree | grep Jun 14, 2014 · You probably need to look at rebalancing your OSD's, as near as I can tell, ceph is trying to calculate space based on how much data you'll have when the first OSD fills up. 2 1 3 1 osd. , OSD IDs, pool names, IP addresses) based on your specific cluster setup. A minimal Ceph OSD Daemon configuration sets host and uses default values for nearly everything else. We need to execute different operations over them and also to retrieve information about physical features and working behavior. The nodes of a hierarchy, called "buckets" in Ceph, are any aggregation of storage locations as defined by their type. 0 up 1 1 1. To set an OSD CRUSH weight in terabytes within the CRUSH map, run the following command, with the value information provided in Table 1: ceph osd crush reweight NAME WEIGHT Troubleshooting OSDs ¶ Before troubleshooting your OSDs, first check your monitors and network. To adjust an OSD’s crush weight in the CRUSH map of a running cluster, execute the following: ceph osd reweight-by-utilization can have bias for reducing weights of high-util OSDs, and not equally consider increasing low-util OSDs. Refer to Adding/Removing OSDs for additional details. $ ceph pg dump > /tmp/pg_dump. Log Collection OSD Information Separate Storage Groups Configuring Pools Custom ceph. 2 up 1 3 1. CRUSH Administration | Storage Strategies Guide | Red Hat Ceph Storage | 5 | Red Hat DocumentationThe CRUSH map contains at least one hierarchy of nodes and leaves. However, even though an OSD is in the cluster, it might be experiencing a malfunction such that you do not want to rely on it as much until you fix it (for example, replace a storage drive, change out a controller, and so on). For example: Monitoring a Cluster After you have a running cluster, you can use the ceph tool to monitor your cluster. I post my crush map and my global configuration and attach my ceph osd list What can i do securely ? I really need yours help thanks by advance Once you have a running cluster, you may use the ceph tool to monitor your cluster. But with a full or near full OSD in hand, increasing pgs is a no-no operation. 04999 host ceph-02 1 0. Using the command line Interactive mode To run the ceph tool in interactive mode, type ceph at the command line with no arguments. 2 from node01 and node02) from the cluster using the ceph osd reweight <osd> 0 command. 5 1 -4 2 Executing this or other weight commands that assign a weight will override the weight assigned by this command (for example, osd reweight-by-utilization, osd crush weight, osd weight, in or out). 1 up 1 2 1 osd. conf, example: Dec 9, 2013 · ceph health HEALTH_WARN 1 near full osd(s) Arrhh, Trying to optimize a little weight given to the OSD. 2 up 1 $ ceph pg dump The ceph osd reweight-by-utilization threshold command automates the process of reducing the weight of OSDs which are heavily overused. 9 TiB 928 KiB 8. Set and change the device class of an OSD, display and sort OSDs by device class. Any experts have any recommendations? Here is what I have so far: root@vhost-1:~# ceph osd df ID CLASS WEIGHT REWEIGHT SIZE RAW USE DATA OMAP META AVAIL %USE VAR PGS STATUS 1 hdd 5. 1 online documentation . For example: Mar 4, 2014 · Hi, after adding an OSD to Ceph it is adviseable to create a relevant entry in Crush map using a weight size depending on disk size. It does *not* change the weights assigned to the buckets above the OSD, and is a corrective measure in case the normal CRUSH distribution isn’t working out quite right. 15 154 up For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. specifying: ceph osd reweight-by-utilization 115 If data distribution is still not ideal step This tool sits between 2 existing tools: Ceph's built-in tool ceph osd reweight-by-utilization with questionable reweight decisions TheJJ/ceph-balancer modifies upmap and can violate your CRUSH rules ceph osd reweight-by-utilization can have bias for reducing weights of high-util OSDs, and not equally consider increasing low-util OSDs. Repair an OSD: ceph osd repairCeph is a self-repairing cluster. This weight is an arbitrary value (generally the size of the disk in TB or something) and controls how much data the system tries to allocate to The CRUSH location for an OSD can be set by adding the crush_location option in ceph. $ ceph osd tree | grep ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … The CRUSH location for an OSD can be set by adding the crush_location option in ceph. For security, select Encryption in the Features section. osd. Red Hat recommends checking the capacity of a cluster regularly to see if it is reaching the upper end of its storage capacity. May 8, 2018 · Expanding Ceph clusters with Juju 13 minute read We just got a set of new SuperMicro servers for one of our Ceph clusters at HUNT Cloud. 04999 host ceph-03 2 0. 13 with a step of 0. See the following sections: EKCO Add-On Prerequisite Reset a Node Reboot a Node Remove a Node from Rook Ceph Clusters Rook Ceph and etcd Node Removal Requirements Rook Ceph Cluster Prerequisites (Recommended) Manually Rebalance Although Ceph uses heartbeats in order to ensure that hosts and daemons are running, the ceph-osd daemons might enter a stuck state where they are not reporting statistics in a timely manner (for example, there might be a temporary network fault). - Use `ceph --help` or `ceph <command> --help` for more options. OSDs should never be full in theory and administrators should monitor how full OSDs are with " ceph osd df tree ". Chapter 2. 8 For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. Using Ceph as a network storage in projects of different load, we can face various tasks that at first glance do not seem simple or trivial. Once you have a running Red Hat Ceph Storage cluster, you might begin monitoring the storage cluster to ensure that the Ceph Monitor and Ceph OSD daemons are running, at a high-level. Ceph OSD Daemons are numerically identified in incremental fashion Jan 12, 2022 · In this post I will show you what can you do whet an OSD is full and the ceph cluster is locked. The weight column is permanent however and I find that to be a good way to manually balance cluster. You have a way to copy 2 NVMe SSDs (I opted for an ORICO NVME SSD Clone device) Check that your Proxmox cluster is OK with pvecm status Check ceph status shows HEALTH_OK Glossary LVM : Linux Volume Manager PV : LVM Physical Volume VG : LVM Volume Group LV : LVM Logical Volume OSD : Ceph Object Storage Daemon PVE : Proxmox Virtual This guide provides information about using the Red Hat OpenStack Platform director to create an overcloud with a containerized Red Hat Ceph Storage cluster. 46 host test2 2 1. 0 up 1 # <-- crush weight is set to "0" 4 0. REWEIGHT: The default reweight value. Using the Command Line Interactive Mode To run the ceph tool in interactive mode, type ceph at the command line with no arguments. 1 up 1 -3 5. Jun 27, 2022 · My problem change a litle after osd. This tool primarily just addresses that deficiency. 05. I don't understand why my pools is near full after adding 4To (replace 4 x1To drive by 4 x 2To, one disk per node) I'm affraid to reweighting my osd like jsterr said. If it was in the storage cluster and recently moved out of the storage cluster, Ceph starts migrating OSD recovery When the cluster starts or when a Ceph OSD terminates unexpectedly and restarts, the OSD begins peering with other Ceph OSDs before a write operation can occur. Mark OSDs down, in, out, lost, purge, reweight, scrub, deep-scrub, destroy, delete, and select profiles to adjust backfilling activity. Retrieve device information. You can reweight OSDs by PG distribution to address this situation by executing the Oct 27, 2024 · 2. List Adding/Removing OSDs ¶ When you have a cluster up and running, you may add OSDs or remove OSDs from the cluster at runtime. 59 1. After running the command, verify the OSD usage again as it may be needed to adjust the threshold further e. reweight-by-pg 按归置组分布情况调整 OSD 的权重 A Ceph OSD’s status is either in the storage cluster, or out of the storage cluster. The new OSD will have the specified uuid, and the command expects a JSON file containing the base64 cephx key for auth entity client. This tool primarily just addresses that deficiency ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … Nov 13, 2025 · For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. 23 in see my ceph status bellow. A common use case is the need to replace one that has been identified as nearing its shelf life. If OSDs are approaching 80% full, it’s time for the administrator to take action to prevent OSDs Chapter 2. By default it will adjust the weights downward on OSDs which reached 120% of the average usage, but if you include threshold it will use that percentage instead. 0 0 reweighted item id 0 name 'osd. That is how a monitor records an OSD’s status. Jul 22, 2018 · “ceph osd reweight” sets an override weight on the OSD. , 1) For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. Is there May 29, 2024 · I used: ceph config set global osd_mclock_profile high_client_ops to ensure the action occurs in production without impacting the VMs I have running. In the case of an OSD failure this is the first place you’ll want to look, as if you need to look at OSD logs or local node failure, this will send you in the right direction. Monitoring OSDs and PGs High availability and high reliability require a fault-tolerant approach to managing hardware and software issues. Feb 20, 2025 · In Ceph, you can set the weight of each OSD to reflect its capacity — this helps the cluster balance data more intelligently. Turn on the balancer, in mode “upmap” so it starts moving the data. For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. 7 GiB 586 GiB 89. reweight != 1)|. If I reweight the OSDs on node1 then data will move to node2-node20. For example: Surviving ceph-osd daemons will report to the monitors that the OSD appears to be down, and a new status will be visible in the output of the ceph health command, as in the following example: ID: The name of the OSD. Executing this or other weight commands that assign a weight will override the weight assigned by this command (for example, osd reweight-by-utilization, osd crush weight, osd weight, in or out). nodes[]|select(. 1 Let’s go slowly, we will increase the weight of osd. If your host has multiple storage drives, you may map one ceph-osd daemon for each drive Subcommand new can be used to create a new OSD or to recreate a previously destroyed OSD with a specific id. Mark OSDs up/down/out, purge and reweight OSDs, perform scrub operations, modify various scrub-related configuration options, select profiles to adjust the level of backfilling activity. *' injectargs '--osd-recovery-max-active 4' Resetting parameters Adding/Removing OSDs When a cluster is up and running, it is possible to add or remove OSDs. Then do the same for node2 through node5. New to Juju? Juju is a cool controller and agent based tool from Canonical to easily deploy and manage applications (called Charms) on different clouds and After purging the OSD with the ceph-volume lvm zap command, if the directory is not present, then you can replace the OSDs with the OSD service specification file with the pre-created LVM. 2-11 all ceph-nodes showing us the same like Monitoring OSDs and PGs High availability and high reliability require a fault-tolerant approach to managing hardware and software issues. Syntax: ceph osd reweight {osd-num} {weight} sudo ceph osd reweight 5 . A notification displays that the OSD was created successfully and the OSD status changes from in and down to in and up a "short" ceph cheat sheet. ceph osd reweight-by-utilization 120 (as an example) Dec 9, 2013 · ceph health HEALTH_WARN 1 near full osd(s) Arrhh, Trying to optimize a little weight given to the OSD. Remove it (and wave bye-bye to all the data in it) with ceph osd pool delete. Chapter 10. If you execute ceph health or ceph -s on the command line and Ceph shows HEALTH_OK, it means that the monitors have a quorum. 1 1 -2 2 host host1 2 1 osd. It is used for adding, removing, exporting or updating of authentication keys Aug 1, 2022 · With the commands below you can set the specific position of an OSD, reweight it's importance or remove it from the crush map all together. More pgs will help distribute full pgs better. Monitoring a cluster typically involves checking OSD status, monitor status, placement group status and metadata server status. 0 to the 512GB drives and 0. [ceph: root@host01 /]# ceph osd tree # id weight type name up/down reweight -1 3 pool default -3 3 rack mainrack -2 3 host osd-host 0 1 osd. 4 up 1 -3 0. Click Create. You must prepare an OSD before you add it to the CRUSH hierarchy. CLASS: The type of devices the OSD uses. This lends itself well for filtering through jq (requires the jq utility). For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack— providing limitless storage for volumes and images with high performance features like copy-on-write cloning. See full list on ceph. Feb 12, 2015 · Create or delete a storage pool: ceph osd pool create || ceph osd pool deleteCreate a new storage pool with a name and number of placement groups with ceph osd pool create. If you search in the list archive, I believe there was a thread last month or so which provided a walkthrough-sort of for dealing with uneven distribution and a full OSD. g. For example, NVMEs or SSDs. 0' to 0 in crush map $ ceph osd tree # id weight type name up/down reweight -1 0. Use Cases: Ceph provides massive storage capacity, and it supports numerous use cases. 04999 osd. 0 1 1 1 osd. 1 up 1 -4 0. CRUSH Administration | Storage Strategies Guide | Red Hat Ceph Storage | 3 | Red Hat DocumentationThe CRUSH map contains at least one hierarchy of nodes and leaves. to 8TB) → run upmap-remapped after. Each leaf of the hierarchy consists If you elect to reweight by utilization, you might need to re-run this command as utilization, hardware or cluster size change. SIZE: The overall storage capacity of the OSD. Contribute to rrmichel/ceph-cheatsheet development by creating an account on GitHub. Likewise, Ceph can provide container-based storage for OpenShift environments. 3 up 1 ``` Now we assign each host to a specific rack: Jun 29, 2021 · 2. 59999 5. This value is in the range 0 to 1, and forces CRUSH to re-place (1-weight) of the data that would otherwise live on this drive. May 8, 2023 · Prerequisites You have a new NVMe SSD of at least the same size. Set the override weight (reweight) of {osd-num} to {weight}. Sep 19, 2023 · Hello, maybe often diskussed but also question from me too: since we have our ceph cluster we can see an unweighted usage of all osd's. This weight is an arbitrary value—generally the size of the disk in TB—and controls how much data the system tries to allocate to the OSD. OMAP: An estimate value of the bluefs storage that is being used to store object map (omap) data (key value pairs The CRUSH location for an OSD can be set by adding the crush_location option in ceph. Specifying a dm-crypt requires specifying the accompanying - Adjust values (e. Description ¶ ceph is a control utility which is used for manual deployment and maintenance of a Ceph cluster. What is your pool size? 304 pgs sound awfuly small for 20 OSDs. Typically, an OSD is a Ceph ceph-osd daemon running on one storage drive within a host machine. 2 up 1 Adding/Removing OSDs When a cluster is up and running, it is possible to add or remove OSDs. osd tree Next up is ceph osd tree, which provides a list of every OSD and also the class, weight, status, which node it’s in, and any reweight or priority. Dec 23, 2014 · $ ceph osd crush reweight osd. 0 root=default datacenter=dc1 room=room1 row=foo rack=bar host=foo-bar-1 Although Ceph uses heartbeats in order to ensure that hosts and daemons are running, the ceph-osd daemons might enter a stuck state where they are not reporting statistics in a timely manner (for example, there might be a temporary network fault). 8)' ID CLASS WEIGHT TYPE NAME STATUS REWEIGHT PRI-AFF -1 0. 0 1. . If your host has multiple storage drives, you may map one ceph-osd daemon for each drive ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … Dec 23, 2014 · Difference Between 'Ceph Osd Reweight' and 'Ceph Osd Crush Reweight' Dec 23, 2014 laurentbarbe From Gregory and Craig in mailing list… “ceph osd crush reweight” sets the CRUSH weight of the OSD. Adjust reweight according to current OSD utilisation - to prevent filling one OSD ceph osd reweight-by-utilization In CRUSH hierarchies with a smaller number of OSDs, it’s possible for some OSDs to get more PGs than other OSDs, resulting in a higher load. Consider running " ceph osd reweight-by-utilization ". In dealing with such problems, we are faced with ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … The total available space with the replication factor, which is three by default, is 84 GiB/3 = 28 GiB USED: The amount of used space in the storage cluster consumed by user data, internal overhead, or reserved capacity. USE: The OSD capacity. This means that tracking down For example, by default, Ceph automatically sets a ceph-osd daemon’s location to be root=default host=HOSTNAME (based on the output from hostname -s). Using the command line ¶ Interactive mode ¶ To run the ceph tool in interactive mode, type ceph at the command line with no arguments. The CRUSH location for an OSD can be defined by adding the crush location option in ceph. 4|osd. If you don’t have a monitor quorum or if there are errors with the monitor status, address the monitor issues first. DATA: The amount of OSD capacity that is used by user data. Managing Ceph OSDs on the dashboard | Dashboard Guide | Red Hat Ceph Storage | 8 | Red Hat DocumentationList OSDs, their status, statistics, information such as attributes, metadata, device health, performance counters and performance details. This made for a great opportunity to write up the simple steps of expanding a Ceph cluster with Juju. Rebalancing load between osd seems to be easy, but do not always go as we would like… Increase osd weight Before operation get the map of Placement Groups. If there's a large imbalance, you may need to look at reweighting. In the OSD Creation Preview dialog review the OSD and click Create. (For instance, if one of your OSDs is Adding/Removing OSDs ¶ When you have a cluster up and running, you may add OSDs or remove OSDs from the cluster at runtime. 0 up 1 1 1 osd. ceph osd reweight as a temporary fix and keep your cluster up and running while waiting for new hardware. You can confirm the location of those OSDs with the ceph osd tree command: # ceph osd tree | grep -Ev '(osd. 000 if the osd goes down and comes back up. The basic use cases we have in this area are: 1. List all drives associated with an OSD. This means that tracking down `ceph osd crush reweight-subtree` the new racks/hosts (e. For example, by default, Ceph automatically sets a ceph-osd daemon’s location to be root=default host=HOSTNAME (based on the output from hostname -s). It does not change Jul 24, 2020 · Data distribution amog Ceph OSDs can be adjusted manually using ceph osd reweight, but I feel easier to run ceph osd reweight-by-utilization from time to time depending on how often data changes in you cluster. WEIGHT: The weight of the OSD in the CRUSH map. May 12, 2025 · Weight adjustments can be made to rebalance the cluster Temporary weight changes (through ceph osd reweight) affect data distribution without changing the CRUSH map Failure Domain Selection Choosing appropriate failure domains impacts resilience: Host-level domains protect against server failures Rack-level domains protect against rack failures IMPORTANT NOTE: With SES 6 and later it is recommended to activate the balancer module instead of making manual OSD weight changes, for details see the SES 7. , 1) # ceph osd tree -f json-pretty | jq '. Deploy OSDs on new drives and hosts. But if your host machine has multiple storage drives, you may map one ceph-osd daemon for each drive on A system with NVMes can, for example, execute more OSD max backfills than a system with HDDs. ceph tell 'osd. 9 TiB 4. Adding OSDs ¶ When you want to expand a cluster, you may add an OSD at runtime. Storage Devices and OSDs Management Workflows The cluster storage devices are the physical storage devices installed in each of the cluster’s hosts. 82 osd. These commands change the parameters on every available OSD in the cluster. Two OSDs with the same weight will receive roughly the same number of I/O requests and store approximately the same amount of data. Oct 6, 2020 · 1. With Ceph, an OSD is generally one Ceph ceph-osd daemon for one storage drive within a host machine. The reweight column is not the right way to handle it as I understand it because that resets to 1. Jun 14, 2014 · You probably need to look at rebalancing your OSD's, as near as I can tell, ceph is trying to calculate space based on how much data you'll have when the first OSD fills up. Run the ceph osd tree command to identify the ceph-osd daemons that are not running. If your host has multiple storage drives, you may map one ceph-osd daemon for each drive For example, the Ceph Block Device client is a leading storage backend for cloud platforms like OpenStack—providing limitless storage for volumes and images with high performance features like copy-on-write cloning. Click Preview. ceph osd crush reweight sets the CRUSH weight of the OSD. Inventory 2. The following resources provide extra context to the disk removal operation: the Cluster Manual Deployment All Ceph clusters require at least one monitor, and at least as many OSDs as copies of an object stored on the cluster. conf, example: More examples Query OSDs Many ceph commands can output json. 15 root default -2 0. 04999 host ceph-01 # <-- the weight of the host changed 0 0 osd. Another example is the desire to scale down the cluster through the removal of a cluster node (machine). 0|osd. Jan 13, 2014 · As you can see racks are empty (and this normal): ```bash $ ceph osd tree id weight type name up/down reweight -6 0 rack rack2 -5 0 rack rack1 -1 11. This includes instructions for customizing your Ceph cluster through the director. The future ceph osd crush [ add | add-bucket | create-or-move | dump | get-tunable | link | move | remove | rename-bucket | reweight | reweight-all | reweight-subtree | rm | rule | set | set-tunable | show-tunables | tunables | unlink ] … ceph osd pool [ create | delete | get | get-quota | ls | mksnap | rename | rmsnap | set | set-quota | stats ] … Aug 15, 2024 · Each OSD in a Ceph cluster typically manages one or more physical or logical storage devices, and the cluster relies on these OSDs to distribute data across the storage pool. 7|osd. type=="osd")|select(. sudo ceph osd crush set osd. *' injectargs '--osd-recovery-max-active 4' Resetting parameters Cephs balancer module isn't always accurate (especially for small clusters) but in the 'ceph osd df' command there is a weight and reweight column. Add OSDs 3. The ceph osd reweight command assigns an override weight to an OSD. conf, example: If you elect to reweight by utilization, you might need to re-run this command as utilization, hardware or cluster size change. Monitoring a cluster typically involves checking OSD status, monitor status, placement group status, and metadata server status. RED HAT CEPH STORAGE CHEAT SHEET Summary of Certain Operations-oriented Ceph Commands Note: Certain command outputs in the Example column were edited for better readability. Remove OSDs 4 This topic describes how to manage nodes on kURL clusters. The OSDs are critical Once you have a running Red Hat Ceph Storage cluster, you might begin monitoring the storage cluster to ensure that the Ceph Monitor and Ceph OSD daemons are running, at a high-level. Monitoring a Cluster After you have a running cluster, you can use the ceph tool to monitor your cluster. The crush location for an OSD is normally expressed via the crush location config option being set in the ceph. It provides a diverse set of commands that allows deployment of monitors, OSDs, placement groups, MDS and overall maintenance, administration of the cluster. 46 host test1 0 1. For the purposes of ceph osd in and ceph osd out, an OSD is either in the cluster or out of the cluster. io Jul 9, 2024 · By using the "Reweight OSDs" feature in QuantaStor, administrators can fine-tune the data distribution and workload balancing within the Ceph storage cluster, helping to optimize performance, improve resource utilization, and achieve better fault tolerance. Commands ¶ auth ¶ Manage authentication keys. Check Ceph OSD individual Disk Usage To view OSD utilization statistics use, ceph osd df For example: The ceph osd reweight-by-utilization threshold command automates the process of reducing the weight of OSDs which are heavily overused. Example: Assign a weight of 1. It does not change A Ceph OSD generally consists of one ceph-osd daemon for one storage drive and its associated journal within a node. If your host has multiple storage drives, you may map one ceph-osd daemon for each drive. 1|osd. For example: migrating data from the old Ceph to the new one with partial use of the previous servers in the new cluster; solving the disk space allocation problem in Ceph. Tuning a Ceph cluster for optimal performance, resilience, and security requires Jun 26, 2025 · Removing a disk ¶ Overview ¶ There are valid reasons for wanting to remove a disk from a Ceph cluster. conf Settings OSD CRUSH Settings Phantom OSD Removal Prerequisites Most of the examples make use of the ceph client command. root=default host= Question: How is the weight defined depending on disk size? Which algorithm can be used to calculate the Adding an OSD to a CRUSH hierarchy is the final step before you start an OSD (rendering it up and in) and Ceph assigns placement groups to the OSD. Deployment tools such as ceph-deploy may perform this step for you. 1 and osd. 23 out then osd. - This list is comprehensive for most manual management tasks but excludes niche tools like `ceph-volume` or `rados`. Query OSDs Many ceph commands can output json. OMAP: An estimate value of the bluefs storage that is being used to store object map (omap) data (key value pairs For example, by default, Ceph automatically sets a ceph-osd daemon’s location to be root=default host=HOSTNAME (based on the output from hostname -s). Bootstrapping the initial monitor (s) is the first step in deploying a Ceph Storage Cluster. Example: ceph osd crush set osd. 4 1 5 1 osd. 73 root default -2 5. Adding OSDs OSDs can be added to a cluster in order to expand the cluster’s capacity and resilience. Apr 3, 2025 · In this example, PG 2. Sep 16, 2014 · The crushtool utility can be used to test Ceph crush rules before applying them to a cluster. Jun 21, 2025 · Ceph is a highly scalable, self-healing distributed storage system designed for object, block, and file workloads. c has OSDs 2 and 3 from DC1, and OSDs 6 and 9 from DC2. *' injectargs '--osd-max-backfills 16' ceph tell 'osd. Adding/Removing OSDs ¶ When you have a cluster up and running, you may add OSDs or remove OSDs from the cluster at runtime. 4 nodes with 7x1TB SSDs (1HE, no space left) 3 nodes with 8X1TB SSDs (2HE, some space left) = 52 SSDs pve 7. ID: The name of the OSD. If your host has multiple storage drives, you may map one ceph-osd daemon for each drive If you elect to reweight by utilization, you might need to re-run this command as utilization, hardware or cluster size change. Specifying a dm-crypt requires specifying the accompanying Subcommand new can be used to create a new OSD or to recreate a previously destroyed OSD with a specific id. Apr 29, 2020 · Tips & tricks for operating Ceph clusters involving taking out its OSDs without data loss, allocating disk space, migrating a VM from LVM to Ceph RBD. 5 TiB 4. May 27, 2020 · In a 20 node cluster with 10 OSDs per node, how would you remove nodes 1-5. When running the above command the threshold value defaults to 120 (e. Ceph has no single point-of-failure, and can service requests for data in a “degraded” mode. It is either up and running, or it is down and not running. 7. $ crushtool --outfn crushmap --build --num_osds 10 \ host straw 2 rack straw 2 default straw 0 id weight type name reweight -9 10 default default -6 4 rack rack0 -1 2 host host0 0 1 osd. id' 3 34 Working with Placement Groups Subcommands of “ceph pg”. conf, example: Sep 27, 2022 · 3) re-weight the OSDs on the two nodes that will be removed (osd. ceph osd reweight sets an override weight on the OSD. It includes procedures for how to safely reset, reboot, and remove nodes when performing maintenance tasks. And here are my OSDs: OSD Config Reference You can configure Ceph OSD Daemons in the Ceph configuration file (or in recent releases, the central config store), but Ceph OSD Daemons can use the default values and a very minimal configuration. You The ceph osd reweight-by-utilization threshold command automates the process of reducing the weight of OSDs which are heavily overused. If a node has multiple storage drives, then map one ceph-osd daemon for each drive. conf. 5|osd. For example, query ceph osd tree for OSDs that have been reweighted from the default (ie. For example, by default, Ceph automatically sets an OSD ’s location to be root=default host=HOSTNAME (based on the output from hostname -s). ooea eiwa dzkpcjg ktgr imjy udlzro hhkyjg woij soew cqk aqeqve fzshv qpx xnp mua