diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index a657f79..04288e5 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -2292,8 +2292,17 @@
             -s "Extra-header:" \
             -c "HTTP/1.0 200 OK"
 
+needs_more_time 2
+run_test    "DTLS proxy: 3d, max handshake, nbio" \
+            -p "$P_PXY drop=5 delay=5 duplicate=5" \
+            "$P_SRV dtls=1 nbio=2 tickets=1 auth_mode=required" \
+            "$P_CLI dtls=1 nbio=2 tickets=1" \
+            0 \
+            -s "Extra-header:" \
+            -c "HTTP/1.0 200 OK"
+
 needs_more_time 4
-run_test    "DTLS proxy: 3d, min handshake, client-initiated renegotiation" \
+run_test    "DTLS proxy: 3d, min handshake, client-initiated renego" \
             -p "$P_PXY drop=5 delay=5 duplicate=5" \
             "$P_SRV dtls=1 tickets=0 auth_mode=none psk=abc123
              renegotiation=1 debug_level=2" \
@@ -2305,6 +2314,19 @@
             -s "Extra-header:" \
             -c "HTTP/1.0 200 OK"
 
+needs_more_time 4
+run_test    "DTLS proxy: 3d, min handshake, client-initiated renego, nbio" \
+            -p "$P_PXY drop=5 delay=5 duplicate=5" \
+            "$P_SRV dtls=1 nbio=2 tickets=0 auth_mode=none psk=abc123
+             renegotiation=1 debug_level=2" \
+            "$P_CLI dtls=1 nbio=2 tickets=0 psk=abc123 renegotiate=1 debug_level=2
+             force_ciphersuite=TLS-PSK-WITH-AES-128-CCM-8" \
+            0 \
+            -c "=> renegotiate" \
+            -s "=> renegotiate" \
+            -s "Extra-header:" \
+            -c "HTTP/1.0 200 OK"
+
 needs_more_time 2
 run_test    "DTLS proxy: 3d, openssl server" \
             -p "$P_PXY drop=5 delay=5 duplicate=5 protect_hvr=1" \
@@ -2323,6 +2345,15 @@
             -s "Extra-header:" \
             -c "HTTP/1.0 200 OK"
 
+needs_more_time 3
+run_test    "DTLS proxy: 3d, openssl server, fragmentation, nbio" \
+            -p "$P_PXY drop=5 delay=5 duplicate=5 protect_hvr=1" \
+            "$O_SRV -dtls1 -mtu 768" \
+            "$P_CLI dtls=1 nbio=2" \
+            0 \
+            -s "Extra-header:" \
+            -c "HTTP/1.0 200 OK"
+
 needs_more_time 2
 run_test    "DTLS proxy: 3d, gnutls server" \
             -p "$P_PXY drop=5 delay=5 duplicate=5" \
@@ -2341,6 +2372,15 @@
             -s "Extra-header:" \
             -c "Extra-header:"
 
+needs_more_time 3
+run_test    "DTLS proxy: 3d, gnutls server, fragmentation, nbio" \
+            -p "$P_PXY drop=5 delay=5 duplicate=5" \
+            "$G_SRV -u --mtu 512" \
+            "$P_CLI dtls=1 nbio=2" \
+            0 \
+            -s "Extra-header:" \
+            -c "Extra-header:"
+
 # Final report
 
 echo "------------------------------------------------------------------------"