add dns entries

Signed-off-by: Joel Fernandes <joel@joelfernandes.org>
diff --git a/buildstrap b/buildstrap
index 90c100a..02dde43 100755
--- a/buildstrap
+++ b/buildstrap
@@ -54,6 +54,9 @@
 	sed -i -e 's/_apt:x:100:65534/_apt:x:100:3003/' $OUT_TMP/etc/passwd
 fi
 
+# Add a default DNS server
+echo "nameserver 4.2.2.2" > $OUT_TMP/etc/resolv.conf
+
 # Clone BCC if needed
 if [[ ! -z ${INSTALL_BCC+x} ]]; then
 git clone https://github.com/iovisor/bcc.git $TDIR/debian/bcc-master