通过ansible升级3.0.13到4.0.7，在 ansible-playbook rolling_update.yml -vvv过程中报以下错误：
<192.168.56.3> SSH: EXEC ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o KbdInteractiveAuthentication=no -o PreferredAuthentications=gssapi-with-mic,gssapi-keyex,hostbased,publickey -o PasswordAuthentication=no -o User=tidb -o ConnectTimeout=10 -o ControlPath=/home/tidb/.ansible/cp/a9fd27561b 192.168.56.3 ‘/bin/sh -c ‘"’"’( umask 77 && mkdir -p “echo /home/tidb/.ansible/tmp/ansible-tmp-1603268188.66-214806267610484” && echo ansible-tmp-1603268188.66-214806267610484=“echo /home/tidb/.ansible/tmp/ansible-tmp-1603268188.66-214806267610484” ) && sleep 0’“'”‘’
<192.168.56.3> (0, ‘ansible-tmp-1603268188.66-214806267610484=/home/tidb/.ansible/tmp/ansible-tmp-1603268188.66-214806267610484
‘, ‘’)
<192.168.56.3> ESTABLISH SSH CONNECTION FOR USER: tidb
<192.168.56.3> SSH: EXEC ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o KbdInteractiveAuthentication=no -o PreferredAuthentications=gssapi-with-mic,gssapi-keyex,hostbased,publickey -o PasswordAuthentication=no -o User=tidb -o ConnectTimeout=10 -o ControlPath=/home/tidb/.ansible/cp/a9fd27561b 192.168.56.3 ‘/bin/sh -c ‘"’“‘rm -f -r /home/tidb/.ansible/tmp/ansible-tmp-1603268188.66-214806267610484/ > /dev/null 2>&1 && sleep 0’”’"’’
<192.168.56.3> (0, ‘’, ‘’)
fatal: [192.168.56.3]: FAILED! => changed=false
msg: ‘AnsibleUndefinedVariable: ‘‘dict object’’ has no attribute ‘‘tiflash_servers’’’
to retry, use: --limit @/home/tidb/tidb-ansible/retry_files/rolling_update.retry
PLAY RECAP ****************************************************************************************
192.168.56.3 : ok=17 changed=1 unreachable=0 failed=1
192.168.56.4 : ok=9 changed=1 unreachable=0 failed=0
192.168.56.5 : ok=9 changed=1 unreachable=0 failed=0
192.168.56.6 : ok=8 changed=0 unreachable=0 failed=0
192.168.56.7 : ok=8 changed=0 unreachable=0 failed=0
192.168.56.8 : ok=8 changed=0 unreachable=0 failed=0
localhost : ok=8 changed=5 unreachable=0 failed=0
ERROR MESSAGE SUMMARY *****************************************************************************
[192.168.56.3]: Ansible Failed! ==>
changed=false
msg: ‘AnsibleUndefinedVariable: ‘‘dict object’’ has no attribute ‘‘tiflash_servers’’’
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[tidb@tidb1_pd1 tidb-ansible]$