Error in Schedule Log

Hi,
I am getting below error. I dont know what it is but I think its related to daily digest mail.

Title frappe.email.queue.flush

Error [Errno -2] Name or service not known
Traceback (most recent call last):
File “/home/itwork/frappe-bench/apps/frappe/frappe/email/queue.py”, line 306, in send_one
smtpserver.sess.sendmail(email.sender, email.recipient, encode(email.message))
File “/home/itwork/frappe-bench/apps/frappe/frappe/email/smtp.py”, line 170, in sess
cint(self.port) or None)
File “/usr/lib/python2.7/smtplib.py”, line 256, in init
(code, msg) = self.connect(host, port)
File “/usr/lib/python2.7/smtplib.py”, line 316, in connect
self.sock = self._get_socket(host, port, self.timeout)
File “/usr/lib/python2.7/smtplib.py”, line 291, in _get_socket
return socket.create_connection((host, port), timeout)
File “/usr/lib/python2.7/socket.py”, line 553, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
ValidationError: [Errno -2] Name or service not known

Might be due to a network issue or service issue at your email provider’s end.