diff --git a/bin/multiweave b/bin/multiweave
index 23a0491a..a0938e30 100755
--- a/bin/multiweave
+++ b/bin/multiweave
@@ -1,6 +1,16 @@
 #!/bin/bash
 set -e
 
+# You may need to adjust
+#    echo 4096 >/proc/sys/net/ipv4/neigh/default/gc_thresh3
+# where the number is greater than NUM_WEAVES*(NUM_WEAVES-1) plus some
+# fudge.
+#
+# Without that, some connections between the weaves may fail to get
+# established, and networking on the host in general becomes
+# broken. There will also be some "net_ratelimit: nnn callbacks
+# suppressed" messages in the syslog.
+
 START=${FIRST_WEAVE:-1}
 COUNT=${NUM_WEAVES:-28}
 FINISH=$((START+COUNT-1))