X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/38da9088282b3a74ddcbfe8d60382b55a7e9f426..9bf74b9c298f6968417fe88a68ccdf2179db1403:/test/scripts/4058-pipe-conn-tfo/4058

diff --git a/test/scripts/4058-pipe-conn-tfo/4058 b/test/scripts/4058-pipe-conn-tfo/4058
index f31ef8d1c..999cfad4a 100644
--- a/test/scripts/4058-pipe-conn-tfo/4058
+++ b/test/scripts/4058-pipe-conn-tfo/4058
@@ -1,13 +1,16 @@
 # Early-pipelining, with TFO
 #
+# NOTE: ensure that TFO is fully enabled in the kernel.
+# For linux: sysctl net.ipv4.tcp_fastopen=3
+# 
 #
 # Packet delays so we can see TFO operational in packet captures
 # Wipe any stored TFO cookie, to start from known state.
 # Disable TFO blackhole-detection as we seem to be running afoul of that
 sudo perl
 system ("tc qdisc add dev lo root netem delay 50ms");
-system ("ip tcp_metrics delete 127.0.0.1");
-system ("echo 0 > /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec");
+system ("ip tcp_metrics delete HOSTIPV4");
+system ("[ -e /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec ] && echo 0 > /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec");
 ****
 #
 #
@@ -72,7 +75,7 @@ killdaemon
 #
 sudo perl
 system ("tc qdisc delete dev lo root");
-system ("echo 3600 > /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec");
+system ("[ -e /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec ] && echo 3600 > /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_sec");
 ****
 #
 no_msglog_check