diff --git a/roles/base/templates/iptables/iptables.bastion b/roles/base/templates/iptables/iptables.bastion
index 05eb9720f0..e6f5d6eed4 100644
--- a/roles/base/templates/iptables/iptables.bastion
+++ b/roles/base/templates/iptables/iptables.bastion
@@ -77,6 +77,8 @@
 -A INPUT -s 192.168.1.0/24 -m tcp -p tcp --dport 25 -j ACCEPT
 -A INPUT -s 192.168.0.0/24 -m tcp -p tcp --dport 25 -j ACCEPT
 -A INPUT -s 10.3.160.0/19 -m tcp -p tcp --dport 25 -j ACCEPT
+# s390x builders/virthost
+-A INPUT -s 10.3.102.0/24 -m tcp -p tcp --dport 25 -j ACCEPT
 # redhat mxes
 -A INPUT -s 10.30.177.0/24 -m tcp -p tcp --dport 25 -j ACCEPT
 -A INPUT -s 10.30.29.0/24 -m tcp -p tcp --dport 25 -j ACCEPT