Upgrade failed when restart master-api service

Issue

• Master-api shows status as below

[root@os3qim04 ~]# systemctl status atomic-openshift-master-api.service
● atomic-openshift-master-api.service - Atomic OpenShift Master API
Loaded: loaded (/usr/lib/systemd/system/atomic-openshift-master-api.service; enabled; vendor preset: disabled)
Active: active (running) since Sun 2017-04-09 20:57:06 CDT; 12h ago
Docs: https://github.com/openshift/origin
Main PID: 117311 (openshift)
Memory: 794.4M
CGroup: /system.slice/atomic-openshift-master-api.service
└─117311 /usr/bin/openshift start master api --config=/etc/origin/master/master-config.yaml --loglevel=2 --listen=https://0.0.0.0:8443 --master=https://master.example.com:8443

Apr 10 09:46:27 os3qim04 atomic-openshift-master-api[117311]: [5.300481687s] [2.302501808s] Object stored in database
Apr 10 09:46:27 os3qim04 atomic-openshift-master-api[117311]: [5.300493918s] [12.231µs] Self-link added
Apr 10 09:46:27 os3qim04 atomic-openshift-master-api[117311]: "Update /api/v1/nodes/master.example.com/status" [5.300829155s] [335.237µs] END
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: I0410 09:46:28.959756 117311 trace.go:61] Trace "Update /api/v1/namespaces/php-app/pods/cakephp-example-2-sh3fq/status" (started 2017-04-10 09:46:28.513364664 -0500 CDT):
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: [30.364µs] [30.364µs] About to convert to expected version
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: [218.668µs] [188.304µs] Conversion done
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: [225.627µs] [6.959µs] About to store object in database
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: [446.141814ms] [445.916187ms] Object stored in database
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: [446.152572ms] [10.758µs] Self-link added
Apr 10 09:46:28 os3qim04 atomic-openshift-master-api[117311]: "Update /api/v1/namespaces/php-app/pods/cakephp-example-2-sh3fq/status" [446.338471ms] [185.899µs] END