CouchBase Monitoring

Overview

CouchBase Server is an open-source, distributed NoSQL document-oriented database and key-value store that is optimized for interactive applications. CouchBase is designed to provide easy-to-scale key-value or document access with low latency and high sustained throughput. Applications Manager helps to actively monitor all aspects of a CouchBase server like health, availability, response time etc., and helps take informed decisions in case of downtimes.

Prerequisites

For Applications Manager to access and monitor the CouchBase server, ensure that the firewall on your network and Applications Manager installed server allows outgoing communication on the TCP port (CouchBase port number).
The URL of the syntax given below should be accessible from the Applications Manager installed machine.
http://<host>:<port>/ui/index.html

Creating a new CouchBase server monitor

Supported Versions: Couchbase v7.0 and below

Using the REST API to add a new CouchBase monitor: Click here

To create a CouchBase server monitor, follow the steps given below:

Click on New Monitor link.
Select CouchBase from Database Servers.
Specify the Display Name of the CouchBase monitor.
Enter the HostName or IP Address of the host where CouchBase process runs.
Enter the Port where the server is running.By default, it will be 8091.
Specify the Polling Interval in minutes.
Choose the Monitor Group with which you want to associate the CouchBase server to, from the combo box (optional). You can choose multiple groups to associate your monitor.
Click Add Monitor(s). This discovers the CouchBase server from the network and starts monitoring it.

Monitored Parameters

Go to the Monitors Category View by clicking the Monitors tab. Click on CouchBase under the Database table. Displayed is the CouchBase bulk configuration view distributed into three tabs:

Availability tab, gives the availability history for the past 24 hours or 30 days.
Performance tab gives the health status and events for the past 24 hours or 30 days.
List view enables you to perform bulk admin configurations.

Click on the monitor name to see all the database details listed under the following tabs:

Monitor Information
Performance Overview
Server Nodes
Data Buckets

Monitor Information:

This tab contains all general information regarding the monitor like Monitor name, port, hostname, username, associated groups etc.

Performance Overview

Parameters	Description
Total Memory (MB)	Total memory available for the cluster.
Used Memory (MB)	RAM usage of the cluster.
Free Memory (MB)	Free memory available.
Cluster Disk Utilization (GB)	Total disk usage of the cluster.
Total Cluster Storage (GB)	Total disk space available for the cluster.
Other Data (GB)	Disk used by other data other than Couchbase.
Usable Free Space (GB)	Maximum free space available for Couchbase server.

Server Nodes

Parameters	Description
Server Node Name	Server IP address where the Couchbase is running.
RAM Usage	RAM usage of the server.
Swap Usage	Swap usage of the server
CPU Usage	CPU usage of the server.
Data Usage	Data usage of this node.
Disk Usage	Disk usage of this node.
Node Memory Utilization	Memory Utilization of the alloted memory.
Active Items	Active data is the data written in this node.
Replica Items	Replica item is the copy of item from another node.
Node Disk Usage	Individual node disk consumed by Couchbase.
Background Data Fetches	Data not in cache and pulled from the disk.

Data Buckets

Parameters	Description
Data Buckets
Bucket Name	Name of the bucket.
Bucket Type	Bucket type can be either Memcached or CouchBase.
Nodes	Number of nodes available in the CouchBase server.
Item Count	Number of objects stored in the bucket.
Used RAM Quota	Memory used from the given quota (in MB).
RAM Quota	Memory allocated for this bucket (in MB).
Quota Memory Utilization	Amount of memory utilized from the available quota (in %).
Data Usage	Data used by this bucket (in MB).
Disk Usage	Disk used by this bucket (in MB).
Docs Fragmentation	Indicates how much fragmented data is to be compacted compared to real data for the data files in this bucket (in %).
OOM/sec	Number of back-offs sent per second to client SDKs due to "out of memory" situations from this bucket.
Current Connections	The number of connections per host.
Resident item ratio	Ratio of items that are kept in memory versus stored on disk.
Total disk drain rate	Number of items actually written to disk from the disk queue.
Memory Headroom	This value indicates when you need to allocate more memory to a bucket.
Bucket Operation Details
Bucket Name	Name of the bucket.
Ops/sec	Number of operations per second for this data bucket.
Gets/sec	Number of reads (GET operations) per second from this bucket.
Total Gets/sec	Total number of GET operations per second from this bucket.
Sets/sec	Number of writes (SET operations) per second to this bucket
Deletes/sec	Number of delete operations per second for this bucket
CAS Ops/sec	Number of operations with a CAS ID per second for this bucket.
Cache Miss Ratio	Ratio of the objects fetched from disk as opposed to memory (in %). Value should be as for be as close to 0 performance.
Bucket Disk Details
Bucket Name	Name of the bucket.
Disk Creates/sec	Number of new items created on disk per second for this bucket.
Disk Updates/sec	Number of items updated on disk per second for this bucket.
Disk Reads/sec	Number of reads per second from disk for this bucket.
Disk Fetches/sec	Number of operations required to fetch the items from disk.
Disk Write Queue	Number of items waiting to be written to disk in this bucket.
Disk Write Failures	Number of disk write failures.
Disk Read Failures	Number of disk read failures.
Disk Usage	Disk used by this bucket (in MB).