diff --git a/ci/test_nsncd.sh b/ci/test_nsncd.sh
index 5858d7b..4be4d6c 100755
--- a/ci/test_nsncd.sh
+++ b/ci/test_nsncd.sh
@@ -16,6 +16,7 @@ for i in $(seq 1 100); do
 	getent services 65000/udp || rc=1
 	getent services foo1/tcp || rc=1
 	getent services foo1/udp || rc=1
+    getent services bufresize/tcp > /dev/null|| rc=1
 	netgroup trusted-machines || rc=1
 	getent netgroup trusted-machines || rc=1
 	innetgr -h machine1 trusted-machines || rc=1
diff --git a/ci/test_nspawn.sh b/ci/test_nspawn.sh
index 1121dca..6240301 100755
--- a/ci/test_nspawn.sh
+++ b/ci/test_nspawn.sh
@@ -19,8 +19,18 @@ sudo sed '$ a netgroup: files' -i /etc/nsswitch.conf
 rc=0
 
 sudo useradd nsncdtest 
-echo -e "foo1\t65000/tcp" | sudo tee -a /etc/services
-echo -e "foo1\t65000/udp" | sudo tee -a /etc/services
+cp /etc/services ./services
+
+# simple service lookups
+echo -e "foo1\t65000/tcp" >> services
+echo -e "foo1\t65000/udp" >> services
+# huge service lookup to exercise buffer resize
+echo -en "bufresize\t65001/tcp " >> services
+for i in $(seq 1000); do echo -n "alias${i} "; done >> services
+echo "" >> services
+sudo mv services /etc/services
+
+tail -5 /etc/services
 echo -e "trusted-machines (machine1,user1,domain1), (machine2,user2,domain2), (machine3,user3,domain3)\n" | sudo tee -a /etc/netgroup
 
 # copy in and execute tests inside the chroot