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Diffstat (limited to 'iredis/data/commands/cluster-count-failure-reports.md')
| -rw-r--r-- | iredis/data/commands/cluster-count-failure-reports.md | 38 |
1 files changed, 13 insertions, 25 deletions
diff --git a/iredis/data/commands/cluster-count-failure-reports.md b/iredis/data/commands/cluster-count-failure-reports.md index bb3c937..ac1ef71 100644 --- a/iredis/data/commands/cluster-count-failure-reports.md +++ b/iredis/data/commands/cluster-count-failure-reports.md @@ -1,33 +1,21 @@ -The command returns the number of _failure reports_ for the specified node. -Failure reports are the way Redis Cluster uses in order to promote a `PFAIL` -state, that means a node is not reachable, to a `FAIL` state, that means that -the majority of masters in the cluster agreed within a window of time that the -node is not reachable. +The command returns the number of *failure reports* for the specified node. +Failure reports are the way Redis Cluster uses in order to promote a +`PFAIL` state, that means a node is not reachable, to a `FAIL` state, +that means that the majority of masters in the cluster agreed within +a window of time that the node is not reachable. A few more details: -- A node flags another node with `PFAIL` when the node is not reachable for a - time greater than the configured _node timeout_, which is a fundamental - configuration parameter of a Redis Cluster. -- Nodes in `PFAIL` state are provided in gossip sections of heartbeat packets. -- Every time a node processes gossip packets from other nodes, it creates (and - refreshes the TTL if needed) **failure reports**, remembering that a given - node said another given node is in `PFAIL` condition. -- Each failure report has a time to live of two times the _node timeout_ time. -- If at a given time a node has another node flagged with `PFAIL`, and at the - same time collected the majority of other master nodes _failure reports_ about - this node (including itself if it is a master), then it elevates the failure - state of the node from `PFAIL` to `FAIL`, and broadcasts a message forcing all - the nodes that can be reached to flag the node as `FAIL`. +* A node flags another node with `PFAIL` when the node is not reachable for a time greater than the configured *node timeout*, which is a fundamental configuration parameter of a Redis Cluster. +* Nodes in `PFAIL` state are provided in gossip sections of heartbeat packets. +* Every time a node processes gossip packets from other nodes, it creates (and refreshes the TTL if needed) **failure reports**, remembering that a given node said another given node is in `PFAIL` condition. +* Each failure report has a time to live of two times the *node timeout* time. +* If at a given time a node has another node flagged with `PFAIL`, and at the same time collected the majority of other master nodes *failure reports* about this node (including itself if it is a master), then it elevates the failure state of the node from `PFAIL` to `FAIL`, and broadcasts a message forcing all the nodes that can be reached to flag the node as `FAIL`. -This command returns the number of failure reports for the current node which -are currently not expired (so received within two times the _node timeout_ -time). The count does not include what the node we are asking this count -believes about the node ID we pass as argument, the count _only_ includes the -failure reports the node received from other nodes. +This command returns the number of failure reports for the current node which are currently not expired (so received within two times the *node timeout* time). The count does not include what the node we are asking this count believes about the node ID we pass as argument, the count *only* includes the failure reports the node received from other nodes. -This command is mainly useful for debugging, when the failure detector of Redis -Cluster is not operating as we believe it should. +This command is mainly useful for debugging, when the failure detector of +Redis Cluster is not operating as we believe it should. @return |