ALM-12190 Number of Knox Connections Exceeds the Threshold

Alarm Description

The system periodically checks the number of connections to all Knox topologies. This alarm is generated when the number of connections to a topology exceeds the threshold (90% by default). This alarm is automatically cleared when the number of connections to a topology falls below the threshold.

This alarm applies to clusters of MRS 3.1.0 or later.

Alarm Attributes

Alarm ID	Alarm Severity	Auto Cleared
12190	Major	Yes

Alarm Parameters

Parameter	Description
Source	Specifies the cluster or system for which the alarm was generated.
ServiceName	Specifies the service for which the alarm was generated.
RoleName	Specifies the role for which the alarm was generated.
HostName	Specifies the host for which the alarm was generated.
Topology	Specifies the Knox topology for which the alarm was generated.

Impact on the System

The topology may reach the upper limit of connections and fail to forward requests, adversely affecting the MRS functions.

Possible Causes

Hue or Manager is too frequently used, but the default maximum number of Knox connections is small.

Handling Procedure

Log in to active and standby OMS nodes as user root, respectively.
Add the following configuration to the gateway-site.xml file on the active and standby OMS nodes to increase the number of thread pools:
vi /opt/knox/conf/gateway-site.xml
```
<property>
<name>gateway.httpclient.maxConnections</name>
<value>64</value>
</property>
```
Log in to the active OMS node as user omm and run the following command to restart the Knox process:
sh /opt/knox/bin/restart-knox.sh
After 5 minutes, check whether the alarm is cleared.
- If yes, no further action is required.
- If no, go to 5.
Contact O&M personnel to rectify the fault.