Swift can't connect to remote server with "object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)"

Issue

• One of the controllers was replaced.
• Controller replaced was never removed from swift rings.
• system logs had messages like this:

controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: Host unreachable
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: ConnectionTimeout (0.5s)
controller-0 swift: ERROR with Account server X.X.X.X:6002/d1 re: Trying to HEAD /v1/.expiring_objects: ConnectionTimeout (0.5s) (txn: tx5737a572027d4382bc1e1-0062325369)
controller-0 swift: ERROR with Account server X.X.X.X:6002/d1 re: Trying to GET /v1/.expiring_objects: Host unreachable (txn: tx142c9595129e4b3389807-0062325369)
controller-0 object-server: ERROR with remote server X.X.X.X:6001/d1: Host unreachable
controller-0 container-server: ERROR reading HTTP response from {'index': 0, u'replication_port': 6001, u'weight': 100.0, u'zone': 1, u'ip': u'X.X.X.X', u'region': 1, u'id': 0, u'replication_ip': u'X.X.X.X', u'meta': u'', u'device': u'd1', u'port': 6001}: Host unreachable
controller-0 account-server: ERROR reading HTTP response from {'index': 2, u'replication_port': 6002, u'weight': 100.0, u'zone': 1, u'ip': u'X.X.X.X', u'region': 1, u'id': 1, u'replication_ip': u'X.X.X.X', u'meta': u'', u'device': u'd1', u'port': 6002}: Host unreachable