Summary
A Report on metrics exported by Native Ceph-Exporter and default Alerts which use them. This report is divided into 2 major sections, 1. Metrics and 2. Alerts.
Section 1: Metrics
The native ceph exporter provides prometheus to scrape hundreds of metrics by default. However, not all of them are of operational importance for someone monitoring the Ceph Deployment. Thus this report contains a limited set of metrics which get used for defining the default set of Alerts. Every metric has a name, a condensed description, a type (of the quantity it represents), and labels. Labels add dimensionality to the otherwise single-dimensional time series.
1. ceph_health_detail:
healthcheck status by type (0=inactive, 1=active). Metric type gauge.
Used by following alerts
CephMonDownQuorumAtRisk, CephMonDiskspaceCritical, CephMonDiskspaceLow, CephMonClockSkew, CephOSDHostDown, CephOSDDown, CephOSDNearFull, CephOSDFull, CephOSDBackfillFull, CephOSDTooManyRepairs, CephOSDTimeoutsPublicNetwork, CephOSDTimeoutsClusterNetwork, CephOSDInternalDiskSizeMismatch, CephDeviceFailurePredicted, CephDeviceFailurePredictionTooHigh, CephDeviceFailureRelocationIncomplete, CephOSDReadErrors, CephFilesystemDamaged, CephFilesystemOffline, CephFilesystemDegraded, CephFilesystemMDSRanksLow, CephFilesystemInsufficientStandby, CephFilesystemFailureNoStandby, CephFilesystemReadOnly, CephMgrModuleCrash, CephPGsDamaged, CephPGRecoveryAtRisk, CephPGUnavilableBlockingIO, CephPGBackfillAtRisk, CephPGNotScrubbed, CephPGsHighPerOSD, CephPGNotDeepScrubbed, CephPoolBackfillFull, CephPoolFull, CephPoolNearFull, CephadmUpgradeFailed, CephadmDaemonFailed, CephadmPaused, CephObjectMissing, and CephObjectMissing
2. ceph_pg_active:
PG active per pool. Metric type gauge.
Used by following alert
sample
ceph_pg_active{pool_id=“1”} 128.0
3. ceph_osd_numpg:
Placement groups. Metric type gauge.
Used by following alert
sample
ceph_osd_numpg{ceph_daemon=“osd.1”} 161.0
4. ceph_osd_up:
OSD status up. Metric type untyped.
Used by following alerts
CephOSDDownHigh, CephOSDFlapping, and CephOSDFlapping
sample
ceph_osd_up{ceph_daemon=“osd.0”} 1.0
5. ceph_pg_total:
PG Total Count per Pool. Metric type gauge.
Used by following alerts
CephPGsInactive, and CephPGsInactive
sample
ceph_pg_total{pool_id=“1”} 128.0
6. ceph_healthcheck_slow_ops:
OSD or Monitor requests taking a long time to process. Metric type gauge.
Used by following alert
sample
ceph_healthcheck_slow_ops 0.0
7. ceph_pool_percent_used:
DF pool percent_used. Metric type gauge.
Used by following alert
sample
ceph_pool_percent_used{pool_id=“1”} 0.0
8. ceph_pool_metadata:
POOL Metadata. Metric type untyped.
Used by following alerts
CephPGsInactive, CephPGsUnclean, and CephPGsUnclean
sample
ceph_pool_metadata{pool_id=“1”,name=“default.rgw.buckets.data”,type=“replicated”,description=“replica:3”,compression_mode=“none”} 1.0
9. ceph_osd_metadata:
OSD Metadata. Metric type untyped.
Used by following alerts
CephOSDFlapping, CephPGImbalance, and CephPGImbalance
sample
ceph_osd_metadata{back_iface="",ceph_daemon=“osd.0”,cluster_addr=“10.5.2.89”,device_class=“hdd”,front_iface="",hostname=“juju-080297-zaza-5e7b19357667-5”,objectstore=“bluestore”,public_addr=“10.5.2.89”,ceph_version=“ceph version 17.2.0 (43e2e60a7559d3f46c9d53f1ca875fd499a1e35e) quincy (stable)”} 1.0
10. ceph_mon_metadata:
MON Metadata. Metric type untyped.
Used by following alerts
CephMonDownQuorumAtRisk, and CephMonDownQuorumAtRisk
sample
ceph_mon_metadata{ceph_daemon=“mon.juju-080297-zaza-5e7b19357667-9”,hostname=“juju-080297-zaza-5e7b19357667-9”,public_addr=“10.5.1.21”,rank=“0”,ceph_version=“ceph version 17.2.0 (43e2e60a7559d3f46c9d53f1ca875fd499a1e35e) quincy (stable)”} 1.0
11. ceph_health_status:
Cluster health status. Metric type untyped.
Used by following alerts
CephHealthError, and CephHealthError
sample
ceph_health_status 0.0
12. ceph_pg_clean:
PG clean per pool. Metric type gauge.
Used by following alert
sample
ceph_pg_clean{pool_id=“1”} 128.0
13. ceph_mon_quorum_status:
Monitors in quorum. Metric type gauge.
Used by following alerts
CephMonDownQuorumAtRisk, and CephMonDownQuorumAtRisk
sample
ceph_mon_quorum_status{ceph_daemon=“mon.juju-080297-zaza-5e7b19357667-9”} 1.0
14. ceph_data_sync_from_zone_fetch_bytes_sum
Number of object bytes replicated Total. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_fetch_bytes_sum{instance_id=“7524”,source_zone=“foo_sec”} 1500.0
15. ceph_data_sync_from_zone_fetch_bytes_count
Number of object bytes replicated Count. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_fetch_bytes_count{instance_id=“7524”,source_zone=“foo_sec”} 10.0
16. ceph_data_sync_from_zone_fetch_errors
Number of object replication errors. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_fetch_errors{instance_id=“7524”,source_zone=“foo_sec”} 2.0
17. ceph_data_sync_from_zone_fetch_not_modified
Number of objects already replicated. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_fetch_not_modified{instance_id=“7524”,source_zone=“foo_sec”} 0.0
18. ceph_data_sync_from_zone_poll_errors
Number of replication log request errors. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_poll_errors{instance_id=“7524”,source_zone=“foo_sec”} 2.0
19. ceph_data_sync_from_zone_poll_latency_sum
Average latency of replication log requests Total. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_poll_latency_sum{instance_id=“7524”,source_zone=“foo_sec”} 18212.350834507
20. ceph_data_sync_from_zone_poll_latency_count
Average latency of replication log requests Count. Metric type counter.
Used by following alerts
sample
ceph_data_sync_from_zone_poll_latency_count{instance_id=“7524”,source_zone=“foo_sec”} 1685428.0
Section 2: Alerts
Ceph has a good number of alert rules configured by default for monitoring a general set of operational events; OSDs reaching near their Full Capacity, Daemon Crashes, and Device Failures to name a few. For a detailed description of individual alerts refer below:
1. CephMonDownQuorumAtRisk (mon)
Summary
Monitor quorum is at risk
Description
Quorum requires a majority of monitors (x) to be active. Without quorum the cluster will become inoperable, affecting all services and connected clients.
2. CephMonDiskspaceCritical (mon)
Summary
Filesystem space on at least one monitor is critically low
Description
The free space available to a monitor’s store is critically low. You should increase the space available to the monitor(s). The default directory is /var/lib/ceph/mon-/data/store.db on traditional deployments, and /var/lib/rook/mon-/data/store.db on the mon pod’s worker node for Rook. Look for old, rotated versions of .log and MANIFEST. Do NOT touch any *.sst files. Also check any other directories under /var/lib/rook and other directories on the same filesystem, often /var/log and /var/tmp are culprits.
3. CephMonDiskspaceLow (mon)
Summary
Drive space on at least one monitor is approaching full
Description
The space available to a monitor’s store is approaching full (>70% is the default). You should increase the space available to the monitor(s). The default directory is /var/lib/ceph/mon-/data/store.db on traditional deployments, and /var/lib/rook/mon-/data/store.db on the mon pod’s worker node for Rook. Look for old, rotated versions of .log and MANIFEST. Do NOT touch any *.sst files. Also check any other directories under /var/lib/rook and other directories on the same filesystem, often /var/log and /var/tmp are culprits.
4. CephMonClockSkew (mon)
Summary
Clock skew detected among monitors
Description
Ceph monitors rely on closely synchronized time to maintain quorum and cluster consistency. This event indicates that the time on at least one mon has drifted too far from the lead mon. Review cluster status with ceph -s. This will show which monitors are affected. Check the time sync status on each monitor host with ‘ceph time-sync-status’ and the state and peers of your ntpd or chrony daemon.
5. CephOSDHostDown (osd)
Summary
An OSD host is offline
Description
Describes the list of OSDs marked offline.
6. CephOSDDown (osd)
Summary
An OSD has been marked down
Description
OSD down for over 5mins. Describes the list of OSDs marked down.
7. CephOSDNearFull (osd)
Summary
OSD(s) running low on free space (NEARFULL)
Description
One or more OSDs have reached the NEARFULL threshold. Use ‘ceph health detail’ and ‘ceph osd df’ to identify the problem. To resolve, add capacity to the affected OSD’s failure domain, restore down/out OSDs, or delete unwanted data.
8. CephOSDFull (osd)
Summary
OSD full, writes blocked
Description
An OSD has reached the FULL threshold. Writes to pools that share the affected OSD will be blocked. Use ‘ceph health detail’ and ‘ceph osd df’ to identify the problem. To resolve, add capacity to the affected OSD’s failure domain, restore down/out OSDs, or delete unwanted data.
9. CephOSDBackfillFull (osd)
Summary
OSD(s) too full for backfill operations
Description
An OSD has reached the BACKFILL FULL threshold. This will prevent rebalance operations from completing. Use ‘ceph health detail’ and ‘ceph osd df’ to identify the problem. To resolve, add capacity to the affected OSD’s failure domain, restore down/out OSDs, or delete unwanted data.
10. CephOSDTooManyRepairs (osd)
Summary
OSD reports a high number of read errors
Description
Reads from an OSD have used a secondary PG to return data to the client, indicating a potential failing drive.
11. CephOSDTimeoutsPublicNetwork (osd)
Summary
Network issues delaying OSD heartbeats (public network)
Description
OSD heartbeats on the cluster’s ‘public’ network (frontend) are running slow. Investigate the network for latency or loss issues. Use ‘ceph health detail’ to show the affected OSDs.
12. CephOSDTimeoutsClusterNetwork (osd)
Summary
Network issues delaying OSD heartbeats (cluster network)
Description
OSD heartbeats on the cluster’s ‘cluster’ network (backend) are slow. Investigate the network for latency issues on this subnet. Use ‘ceph health detail’ to show the affected OSDs.
13. CephOSDInternalDiskSizeMismatch (osd)
Summary
OSD size inconsistency error
Description
One or more OSDs have an internal inconsistency between metadata and the size of the device. This could lead to the OSD(s) crashing in future. You should redeploy the affected OSDs.
14. CephDeviceFailurePredicted (osd)
Summary
Device(s) predicted to fail soon
Description
The device health module has determined that one or more devices will fail soon. To review device status use ‘ceph device ls’. To show a specific device use 'ceph device info '. Mark the OSD out so that data may migrate to other OSDs. Once the OSD has drained, destroy the OSD, replace the device, and redeploy the OSD.
15. CephDeviceFailurePredictionTooHigh (osd)
Summary
Too many devices are predicted to fail, unable to resolve
Description
The device health module has determined that devices predicted to fail can not be remediated automatically, since too many OSDs would be removed from the cluster to ensure performance and availabililty. Prevent data integrity issues by adding new OSDs so that data may be relocated.
16. CephDeviceFailureRelocationIncomplete (osd)
Summary
Device failure is predicted, but unable to relocate data
Description
The device health module has determined that one or more devices will fail soon, but the normal process of relocating the data on the device to other OSDs in the cluster is blocked. Ensure that the cluster has available free space. It may be necessary to add capacity to the cluster to allow data from the failing device to successfully migrate, or to enable the balancer.
17. CephOSDReadErrors (osd)
Summary
Device read errors detected
Description
An OSD has encountered read errors, but the OSD has recovered by retrying the reads. This may indicate an issue with hardware or the kernel.
18. CephFilesystemDamaged (mds)
Summary
CephFS filesystem is damaged.
Description
Filesystem metadata has been corrupted. Data may be inaccessible. Analyze metrics from the MDS daemon admin socket, or escalate to support.
19. CephFilesystemOffline (mds)
Summary
CephFS filesystem is offline
Description
All MDS ranks are unavailable. The MDS daemons managing metadata are down, rendering the filesystem offline.
20. CephFilesystemDegraded (mds)
Summary
CephFS filesystem is degraded
Description
One or more metadata daemons (MDS ranks) are failed or in a damaged state. At best the filesystem is partially available, at worst the filesystem is completely unusable.
21. CephFilesystemMDSRanksLow (mds)
Summary
Ceph MDS daemon count is lower than configured
Description
The filesystem’s ‘max_mds’ setting defines the number of MDS ranks in the filesystem. The current number of active MDS daemons is less than this value.
22. CephFilesystemInsufficientStandby (mds)
Summary
Ceph filesystem standby daemons too few
Description
The minimum number of standby daemons required by standby_count_wanted is less than the current number of standby daemons. Adjust the standby count or increase the number of MDS daemons.
23. CephFilesystemFailureNoStandby (mds)
Summary
MDS daemon failed, no further standby available
Description
An MDS daemon has failed, leaving only one active rank and no available standby. Investigate the cause of the failure or add a standby MDS.
24. CephFilesystemReadOnly (mds)
Summary
CephFS filesystem in read only mode due to write error(s)
Description
The filesystem has switched to READ ONLY due to an unexpected error when writing to the metadata pool. Either analyze the output from the MDS daemon admin socket, or escalate to support.
25. CephMgrModuleCrash (mgr)
Summary
A manager module has recently crashed
Description
One or more mgr modules have crashed and have yet to be acknowledged by an administrator. A crashed module may impact functionality within the cluster. Use the ‘ceph crash’ command to determine which module has failed, and archive it to acknowledge the failure.
26. CephPGsDamaged (pgs)
Summary
Placement group damaged, manual intervention needed
Description
During data consistency checks (scrub), at least one PG has been flagged as being damaged or inconsistent. Check to see which PG is affected, and attempt a manual repair if necessary. To list problematic placement groups, use 'rados list-inconsistent-pg '. To repair PGs use the ‘ceph pg repair <pg_num>’ command.
27. CephPGRecoveryAtRisk (pgs)
Summary
OSDs are too full for recovery
Description
Data redundancy is at risk since one or more OSDs are at or above the ‘full’ threshold. Add more capacity to the cluster, restore down/out OSDs, or delete unwanted data.
28. CephPGUnavilableBlockingIO (pgs)
Summary
PG is unavailable, blocking I/O
Description
Data availability is reduced, impacting the cluster’s ability to service I/O. One or more placement groups (PGs) are in a state that blocks I/O.
29. CephPGBackfillAtRisk (pgs)
Summary
Backfill operations are blocked due to lack of free space
Description
Data redundancy may be at risk due to lack of free space within the cluster. One or more OSDs have reached the ‘backfillfull’ threshold. Add more capacity, or delete unwanted data.
30. CephPGNotScrubbed (pgs)
Summary
Placement group(s) have not been scrubbed
Description
One or more PGs have not been scrubbed recently. Scrubs check metadata integrity, protecting against bit-rot. They check that metadata is consistent across data replicas. When PGs miss their scrub interval, it may indicate that the scrub window is too small, or PGs were not in a ‘clean’ state during the scrub window. You can manually initiate a scrub with: ceph pg scrub
31. CephPGsHighPerOSD (pgs)
Summary
Placement groups per OSD is too high
Description
The number of placement groups per OSD is too high (exceeds the mon_max_pg_per_osd setting). Check that the pg_autoscaler has not been disabled for any pools with ‘ceph osd pool autoscale-status’, and that the profile selected is appropriate. You may also adjust the target_size_ratio of a pool to guide the autoscaler based on the expected relative size of the pool (‘ceph osd pool set cephfs.cephfs.meta target_size_ratio .1’) or set the pg_autoscaler mode to ‘warn’ and adjust pg_num appropriately for one or more pools.
32. CephPGNotDeepScrubbed (pgs)
Summary
Placement group(s) have not been deep scrubbed
Description
One or more PGs have not been deep scrubbed recently. Deep scrubs protect against bit-rot. They compare data replicas to ensure consistency. When PGs miss their deep scrub interval, it may indicate that the window is too small or PGs were not in a ‘clean’ state during the deep-scrub window.
33. CephPoolBackfillFull (pools)
Summary
Free space in a pool is too low for recovery/backfill
Description
A pool is approaching the near full threshold, which will prevent recovery/backfill operations from completing. Consider adding more capacity.
34. CephPoolFull (pools)
Summary
Pool is full - writes are blocked
Description
A pool has reached its MAX quota, or OSDs supporting the pool have reached the FULL threshold. Until this is resolved, writes to the pool will be blocked. Pool Breakdown (top 5) - at % Increase the pool’s quota, or add capacity to the cluster first then increase the pool’s quota (e.g. ceph osd pool set quota <pool_name> max_bytes )
35. CephPoolNearFull (pools)
Summary
One or more Ceph pools are nearly full
Description
A pool has exceeded the warning (percent full) threshold, or OSDs supporting the pool have reached the NEARFULL threshold. Writes may continue, but you are at risk of the pool going read-only if more capacity isn’t made available. Determine the affected pool with ‘ceph df detail’, looking at QUOTA BYTES and STORED. Increase the pool’s quota, or add capacity to the cluster first then increase the pool’s quota (e.g. ceph osd pool set quota <pool_name> max_bytes ). Also ensure that the balancer is active.
36. CephadmUpgradeFailed (cephadm)
Summary
Ceph version upgrade has failed
Description
The cephadm cluster upgrade process has failed. The cluster remains in an undetermined state. Please review the cephadm logs, to understand the nature of the issue
37. CephadmDaemonFailed (cephadm)
Summary
A ceph daemon manged by cephadm is down
Description
A daemon managed by cephadm is no longer active. Determine, which daemon is down with ‘ceph health detail’. you may start daemons with the ‘ceph orch daemon start <daemon_id>’
38. CephadmPaused (cephadm)
Summary
Orchestration tasks via cephadm are PAUSED
Description
Cluster management has been paused manually. This will prevent the orchestrator from service management and reconciliation. If this is not intentional, resume cephadm operations with ‘ceph orch resume’
39. CephObjectMissing (rados)
Summary
Object(s) marked UNFOUND
Description
The latest version of a RADOS object can not be found, even though all OSDs are up. I/O requests for this object from clients will block (hang). Resolving this issue may require the object to be rolled back to a prior version manually, and manually verified.
40. CephDaemonCrash (generic)
Summary
One or more Ceph daemons have crashed, and are pending acknowledgement
Description
One or more daemons have crashed recently, and need to be acknowledged. This notification ensures that software crashes do not go unseen. To acknowledge a crash, use the 'ceph crash archive ’ command.
41. CephPGsInactive (pgs)
Summary
One or more placement groups are inactive
Description
PGs have been inactive for more than 5 minutes in pool . Inactive placement groups are not able to serve read/write requests.
42. CephPGImbalance (osd)
Summary
PGs are not balanced across OSDs
Description
OSD on deviates by more than 30% from average PG count.
43. CephOSDDownHigh (osd)
Summary
More than 10% of OSDs are down
Description
% or of OSDs are down (>= 10%). The following OSDs are down: - on
44. CephOSDFlapping (osd)
Summary
Network issues are causing OSDs to flap (mark each other down)
Description
OSD on was marked down and back up times once a minute for 5 minutes. This may indicate a network issue (latency, packet loss, MTU mismatch) on the cluster network, or the public network if no cluster network is deployed. Check the network stats on the listed host(s).
45. CephPGsUnclean (pgs)
Summary
One or more placement groups are marked unclean
Description
PGs have been unclean for more than 15 minutes in pool . Unclean PGs have not recovered from a previous failure.
46. CephSlowOps (healthchecks)
Summary
OSD operations are slow to complete
Description
OSD requests are taking too long to process (osd_op_complaint_time exceeded)
47. CephPoolGrowthWarning (pools)
Summary
Pool growth rate may soon exceed capacity
Description
Pool ‘’ will be full in less than 5 days assuming the average fill-up rate of the past 48 hours.
48. CephMonDown (mon)
Summary
One or more monitors down
Description
You have monitor down. Quorum is still intact, but the loss of an additional monitor will make your cluster inoperable. The following monitors are down: - on
49. CephHealthError (cluster health)
Summary
Ceph is in the ERROR state
Description
The cluster state has been HEALTH_ERROR for more than 5 minutes. Please check ‘ceph health detail’ for more information.
50. CephHealthWarning (cluster health)
Summary
Ceph is in the WARNING state
Description
The cluster state has been HEALTH_WARN for more than 15 minutes. Please check ‘ceph health detail’ for more information.
51. CephRGWMultisitePollError
Summary
Unsuccessful Replication Log Request Errors Threshold Exceeded
Description
Unsuccessful replication log request errors threshold has been exceeded. The threshold is defined as 2 errors per 15min
52. CephRGWMultisitePollErrorCritical
Summary
Critical: Unsuccessful Replication Log Request Errors Threshold Exceeded
Description
Critical: Unsuccessful replication log request errors threshold has been exceeded. The threshold is defined as 50 errors per 15min
53. CephRGWMultisiteFetchError
Summary
Unsuccessful Object Replications from Source Zone Threshold Exceeded
Description
Unsuccessful Object Replications from source zone threshold has been exceeded. The threshold is defined as 2 errors per 15min
54. CephRGWMultisiteFetchErrorCritical
Summary
Critical: Unsuccessful Object Replications from Source Zone Threshold Exceeded
Description
Critical: Unsuccessful Object Replications from source zone threshold has been exceeded. The threshold is defined as 50 errors per 15min
55. CephRGWMultisitePollLatency
Summary
Poll Request Latency Threshold Exceeded
Description
Latency for poll request threshold exceeded. The threshold is defined as 600s latency per 15min