Warn when connection to Spamhaus times out (#1817)

management/status_checks.py

@@ -293,6 +293,8 @@ def run_network_checks(env, output):
 	zen = query_dns(rev_ip4+'.zen.spamhaus.org', 'A', nxdomain=None)
 	if zen is None:
 		output.print_ok("IP address is not blacklisted by zen.spamhaus.org.")
+	elif zen == "[timeout]":
+		output.print_warning("Connection to zen.spamhaus.org timed out. We could not determine whether your server's IP address is blacklisted. Please try again later.")
 	else:
 		output.print_error("""The IP address of this machine %s is listed in the Spamhaus Block List (code %s),
 			which may prevent recipients from receiving your email. See http://www.spamhaus.org/query/ip/%s."""
@@ -678,6 +680,8 @@ def check_mail_domain(domain, env, output):
 	dbl = query_dns(domain+'.dbl.spamhaus.org', "A", nxdomain=None)
 	if dbl is None:
 		output.print_ok("Domain is not blacklisted by dbl.spamhaus.org.")
+	elif dbl == "[timeout]":
+		output.print_warning("Connection to dbl.spamhaus.org timed out. We could not determine whether the domain {} is blacklisted. Please try again later.".format(domain))
 	else:
 		output.print_error("""This domain is listed in the Spamhaus Domain Block List (code %s),
 			which may prevent recipients from receiving your mail.