EL7,8: no such package iptables-ipv6

el/rtpengine.spec

@@ -32,12 +32,14 @@ The Sipwise NGCP rtpengine is a proxy for RTP traffic and other UDP based
 media traffic. It's meant to be used with the Kamailio SIP proxy and forms a
 drop-in replacement for any of the other available RTP and media proxies.
 
-
+%if 0%{?rhel} < 7
+%define iptables_ipv6 1
+%endif
 %package kernel
 Summary:	NGCP rtpengine in-kernel packet forwarding
 Group:		System Environment/Daemons
 BuildRequires:	gcc make redhat-rpm-config iptables-devel
-Requires:	iptables iptables-ipv6
+Requires:	iptables %{?iptables_ipv6:iptables-ipv6}
 Requires:	%{name}%{?_isa} = %{version}-%{release}
 Requires: 	%{name}-dkms = %{version}-%{release}