From 27c885ff0844c3391a8fc4ef1165edb354455ec5 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Fri, 31 Jan 2020 23:17:12 +0100 Subject: [PATCH] man: document dynamic debug trick for Linux This comes up occasionally, so it may be useful to mention its possibility in the man page. At least the Arch Linux and Ubuntu kernels support dynamic debugging, so this advise will at least help somebody. Signed-off-by: Jason A. Donenfeld --- src/man/wg.8 | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/man/wg.8 b/src/man/wg.8 index 07b9694..27860c8 100644 --- a/src/man/wg.8 +++ b/src/man/wg.8 @@ -212,6 +212,15 @@ are thus ignored. .br AllowedIPs = 10.10.10.230/32 +.SH DEBUGGING INFORMATION +Sometimes it is useful to have information on the current runtime state of a tunnel. When using the Linux kernel module on a kernel that supports dynamic debugging, debugging information can be written into +.BR dmesg (1) +by running as root: + +\fB # modprobe wireguard && echo module wireguard +p > /sys/kernel/debug/dynamic_debug/control\fP + +On userspace implementations, it is customary to set the \fILOG_LEVEL\fP environment variable to \fIdebug\fP. + .SH ENVIRONMENT VARIABLES .TP .I WG_COLOR_MODE