ansible Failed to connect to the host via ssh: no such identity: /root/.ssh/id_rsa.bak

ansible -i inventory.cfg all -m ping
10.1.1.1 | UNREACHABLE! => {
    "changed": false, 
    "msg": "Failed to connect to the host via ssh: no such identity: /root/.ssh/id_rsa.bak: No such file or directory\r\nPermission denied (publickey,gssapi-keyex,gssapi-with-mic,password).\r\n", 
    "unreachable": true
}

ansible -vvv -i inventory.cfg all -m ping 
ansible 2.6.2
  config file = /home/bichenchen001/mongodb_auto_deploy/ansible.cfg
  configured module search path = [u‘/root/.ansible/plugins/modules‘, u‘/usr/share/ansible/plugins/modules‘]
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /bin/ansible
  python version = 2.7.5 (default, Apr 11 2018, 07:36:10) [GCC 4.8.5 20150623 (Red Hat 4.8.5-28)]
Using /home/bichenchen001/mongodb_auto_deploy/ansible.cfg as config file
Parsed /home/bichenchen001/mongodb_auto_deploy/inventory.cfg inventory source with ini plugin
META: ran handlers
<10.1.1.1> ESTABLISH SSH CONNECTION FOR USER: None
<10.1.1.1> SSH: EXEC ssh -C -o ControlMaster=auto -o ControlPersist=60s -o ‘IdentityFile="/root/.ssh/id_rsa.bak"‘ -o KbdInteractiveAuthentication=no -o PreferredAuthentications=gssapi-with-mic,gssapi-keyex,hostbased,publickey -o PasswordAuthentication=no -o ConnectTimeout=10 -o 

cp /root/.ssh/id_rsa /root/.ssh/id_rsa.bak