Run the following command to monitor the available entropy on the server.
watch -n 1 cat /proc/sys/kernel/random/entropy_avail
In addition, a kill -3 can be issued against the hung cybAgent.bin process which will cause it to dump thread info to <AGENT_HOME>/nohup.stdout. In that file, search for the following...
MainThread" prio=10 tid=0xf6908c00 nid=0x3153 runnable [0xf740e000]
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(Unknown Source)
at sun.security.provider.SeedGenerator$URLSeedGenerator.getSeedBytes(Unknown Source)
If the above is in the nohup.stdout file after the thread info dump, it confirms that the agent is hanging while trying to initialize encryption routines.
Ideally, the available entropy on the server should be at a minimum of 300 to avoid issues with the agent initializing the encryption routines.
Consult System Administrator to enable 'rngd' service to increase the entropy.
systemctl enable rngd.service