The vCenter Envoy service must set a limit on remote connections.

Envoy client connections must be limited to preserve system resources and continue servicing connections without interruption. Without a limit set, the system would be vulnerable to a trivial denial-of-service attack where connections are created en masse and vCenter resources are entirely consumed.

Envoy comes hard coded with a tested and supported value for "maxRemoteHttpsConnections" and "maxRemoteHttpConnections" that must be verified and maintained.

At the command prompt, run the following commands:

# xmllint --xpath '/config/envoy/L4Filter/maxRemoteHttpsConnections/text()' /etc/vmware-rhttpproxy/config.xml
# xmllint --xpath '/config/envoy/L4Filter/maxRemoteHttpConnections/text()' /etc/vmware-rhttpproxy/config.xml

Example result:

2048

or

XPath set is empty

If the output is not "2048" or "XPath set it empty", this is a finding.

Note: If "XPath set is empty" is returned the default values are in effect and is 2048.

Navigate to and open:

/etc/vmware-rhttpproxy/config.xml

Locate the <config>/<envoy>/<L4Filter> block and configure it as follows:

<maxRemoteHttpsConnections>2048</maxRemoteHttpsConnections> <maxRemoteHttpConnections>2048</maxRemoteHttpConnections>

Restart the service for changes to take effect.

# vmon-cli --restart rhttpproxy