Agents Communication Issues After Upgrade from Enterprise Manager 13c Release 2 to 13c Release 4

Upon upgrade from 13c Release 2 to 13c Release 4 certain agent home pages display the following message:

Communication between the Oracle Management Service to the Agent is unavailable. Any features or displayed information requiring this communication will be unavailable.

This error occurs for Agent versions 13c Release 2 BP3 or below.

To resolve this issue, navigate to each agent version 13c Release 2 BP3 or below and perform the following:

1. Stop the agent: emctl stop agent

2.<AgentInstanceHome>/bin/emctl setproperty agent -name "SSLCipherSuites" -value "SSL_RSA_WITH_AES_128_CBC_SHA:SSL_RSA_WITH_AES_256_CBC_SHA:TLS_RSA_WITH_AES_128_CBC_SHA256:TLS_RSA_WITH_AES_256_CBC_SHA256:TLS_RSA_WITH_AES_128_GCM_SHA256:TLS_RSA_WITH_AES_256_GCM_SHA384:TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA:TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA:TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384:TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256:TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA:TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA:TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256:TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384:TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256:TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384"

3. Start the agent: <AgentInstanceHome>/bin/emctl start agent

4. Check the agent to OMS communication: <AgentInstanceHome>/bin/emctl pingOMS

(Bug 30796644)