diff --git a/inventory/group_vars/all b/inventory/group_vars/all
index 6d84dc62b1..4d6560e4bd 100644
--- a/inventory/group_vars/all
+++ b/inventory/group_vars/all
@@ -55,6 +55,13 @@ mem_size: 2048
 num_cpus: 2
 lvm_size: 20000
 
+# on MOST infra systems, the interface connected to the infra network
+# is eth0. but not on quite ALL systems. e.g. on s390 boxes it's enc900,
+# on openqa-ppc64le-01.qa it's eth2 for some reason, and on qa01.qa and
+# qa02.qa it's em3. currently this only affects whether GATEWAY, DOMAIN
+# and DNS1/DNS2 lines are put into ifcfg-(device).
+ansible_ifcfg_infra_net_devices: [ 'eth0', 'enc900' ]
+
 # Default netmask. Almost all our phx2 nets are /24's with the
 # exception of 10.5.124.128/25. Almost all of our non phx2 sites are
 # less than a /24.
diff --git a/inventory/host_vars/openqa-ppc64le-01.qa.fedoraproject.org b/inventory/host_vars/openqa-ppc64le-01.qa.fedoraproject.org
index bf3ce9d2db..1b545a4b07 100644
--- a/inventory/host_vars/openqa-ppc64le-01.qa.fedoraproject.org
+++ b/inventory/host_vars/openqa-ppc64le-01.qa.fedoraproject.org
@@ -1,5 +1,7 @@
 ---
 freezes: false
+# the if connected to the infra network on this box is eth2, not eth0
+ansible_ifcfg_infra_net_devices: [ 'eth2' ]
 gw: 10.5.131.254
 dns: 10.5.126.21
 eth2_ip: 10.5.131.73
diff --git a/inventory/host_vars/qa01.qa.fedoraproject.org b/inventory/host_vars/qa01.qa.fedoraproject.org
index b9c991227d..856ad71e58 100644
--- a/inventory/host_vars/qa01.qa.fedoraproject.org
+++ b/inventory/host_vars/qa01.qa.fedoraproject.org
@@ -5,6 +5,9 @@ sudoers: "{{ private }}/files/sudo/qavirt-sudoers"
 
 nrpe_procs_warn: 1400
 nrpe_procs_crit: 1600
+
+# the if connected to the infra network on this box is em3, not eth0
+ansible_ifcfg_infra_net_devices: [ 'em3' ]
 em3_ip: 10.5.124.151
 em3_nm: 255.255.255.0
 gw: 10.5.124.254
diff --git a/inventory/host_vars/qa02.qa.fedoraproject.org b/inventory/host_vars/qa02.qa.fedoraproject.org
index 9cc5b4fa0a..9122800412 100644
--- a/inventory/host_vars/qa02.qa.fedoraproject.org
+++ b/inventory/host_vars/qa02.qa.fedoraproject.org
@@ -5,6 +5,9 @@ sudoers: "{{ private }}/files/sudo/qavirt-sudoers"
 
 nrpe_procs_warn: 1400
 nrpe_procs_crit: 1600
+
+# the if connected to the infra network on this box is em3, not eth0
+ansible_ifcfg_infra_net_devices: [ 'em3' ]
 em3_ip: 10.5.124.152
 em3_nm: 255.255.255.0
 gw: 10.5.124.254
diff --git a/roles/base/templates/ifcfg.j2 b/roles/base/templates/ifcfg.j2
index 9656c35e4d..2f334be67b 100644
--- a/roles/base/templates/ifcfg.j2
+++ b/roles/base/templates/ifcfg.j2
@@ -6,7 +6,7 @@ SUBCHANNELS="0.0.0900,0.0.0901,0.0.0902"
 NETTYPE="qeth"
 OPTIONS="layer2=1 portno=0"
 {% endif %}
-{% if item == "eth0" or item == "enc900" %}
+{% if item in ansible_ifcfg_infra_net_devices %}
 GATEWAY="{{gw}}"
 DOMAIN="phx2.fedoraproject.org vpn.fedoraproject.org fedoraproject.org"
 DNS1="{{ dns1 }}"