system-health service stopped:
------------------------------
root@sonic:/home/admin# systemctl stop system-health.service
root@sonic:/home/admin#

root@sonic:/home/admin# show system-health sysready-status
No info
root@sonic:/home/admin#
root@sonic:/home/admin# sonic-db-cli STATE_DB hgetall 'ALL_SERVICE_STATUS|bgp'
{}
root@sonic:/home/admin#



Start system-health service:
----------------------------
root@sonic:/home/admin# systemctl start system-health.service
root@sonic:/home/admin#
May 05 12:11:38.822073 System is ready

root@sonic:/home/admin#
root@sonic:/home/admin# sonic-db-cli STATE_DB hgetall 'ALL_SERVICE_STATUS|bgp'
{'app_ready_status': 'OK', 'fail_reason': '-', 'service_status': 'OK', 'update_time': '-'}
root@sonic:/home/admin#


root@sonic:/home/admin# show log | grep "System is ready"
May  5 06:38:12.531618 sonic NOTICE healthd[3125]: System is ready

root@sonic:/home/admin# sonic-db-cli STATE_DB hgetall "SYSTEM_READY|SYSTEM_STATE"
{'Status': 'UP'}
root@sonic:/home/admin#

root@sonic:/home/admin# show system-health sysready-status
System is ready

Service-Name                      Service-Status    App-Ready-Status    Down-Reason
--------------------------------  ----------------  ------------------  -------------
as7326-56x-pddf-platform-monitor  OK                OK                  -
auditd                            OK                OK                  -
bgp                               OK                OK                  -
caclmgrd                          OK                OK                  -
config-chassisdb                  OK                OK                  -
config-setup                      OK                OK                  -
containerd                        OK                OK                  -
cron                              OK                OK                  -
database                          OK                OK                  -
docker                            OK                OK                  -
kdump-tools                       OK                OK                  -
lldp                              OK                OK                  -
mgmt-framework                    OK                OK                  -
ntp                               OK                OK                  -
opennsl-modules                   OK                OK                  -
pddf-platform-init                OK                OK                  -
pmon                              OK                OK                  -
procdockerstatsd                  OK                OK                  -
radv                              OK                OK                  -
ras-mc-ctl                        OK                OK                  -
rasdaemon                         OK                OK                  -
rsyslog                           OK                OK                  -
smartmontools                     OK                OK                  -
snmp                              OK                OK                  -
ssh                               OK                OK                  -
swss                              OK                OK                  -
syncd                             OK                OK                  -
teamd                             OK                OK                  -
telemetry                         OK                OK                  -
root@sonic:/home/admin#



Stop a service and check for system ready:
-----------------------------------------
root@sonic:/home/admin# systemctl stop bgp
root@sonic:/home/admin#
May 05 13:11:30.347492 System is not ready - one or more services are not up

root@sonic:/home/admin#
root@sonic:/home/admin# sonic-db-cli STATE_DB hgetall 'ALL_SERVICE_STATUS|bgp'
{'app_ready_status': 'Down', 'fail_reason': 'Inactive', 'service_status': 'Down', 'update_time': '-'}
root@sonic:/home/admin#

root@sonic:/home/admin# show log | grep "System is not ready"
May  5 13:11:30.347720 sonic NOTICE healthd[119562]: System is not ready - one or more services are not up


root@sonic:/home/admin# sonic-db-cli STATE_DB hgetall "SYSTEM_READY|SYSTEM_STATE"
{'Status': 'DOWN'}
root@sonic:/home/admin#

root@sonic:/home/admin# show system-health sysready-status
System is not ready - one or more services are not up

Service-Name                      Service-Status    App-Ready-Status    Down-Reason
--------------------------------  ----------------  ------------------  -------------
as7326-56x-pddf-platform-monitor  OK                OK                  -
auditd                            OK                OK                  -
bgp                               Down              Down                Inactive
caclmgrd                          OK                OK                  -
config-chassisdb                  OK                OK                  -
config-setup                      OK                OK                  -
containerd                        OK                OK                  -
cron                              OK                OK                  -
database                          OK                OK                  -
docker                            OK                OK                  -
kdump-tools                       OK                OK                  -
lldp                              OK                OK                  -
mgmt-framework                    OK                OK                  -
ntp                               OK                OK                  -
opennsl-modules                   OK                OK                  -
pddf-platform-init                OK                OK                  -
pmon                              OK                OK                  -
procdockerstatsd                  OK                OK                  -
radv                              OK                OK                  -
ras-mc-ctl                        OK                OK                  -
rasdaemon                         OK                OK                  -
rsyslog                           OK                OK                  -
smartmontools                     OK                OK                  -
snmp                              OK                OK                  -
ssh                               OK                OK                  -
swss                              OK                OK                  -
syncd                             OK                OK                  -
teamd                             OK                OK                  -
telemetry                         OK                OK                  -
root@sonic:/home/admin#