Hi Nam Tran Quoc,
I am faced this problem when QRadar got new network interface without correct routing configuration and Console didn't saw docker containers with application.
Check gateways and connection with the containers.
Test status of docker and apps:
systemctl status docker
/opt/qradar/support/recon ps
drq -v
Connect direct to app container and test network.
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Alexandr Lebedev
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