OpenVPN server log - what is the "us=" identifier following the timestamp?

Question

I use OpenVPN 2.3.10 in server mode, with logging set to verb 4.

In the log, every line begins by a timestamp (Mon May 11 10:40:10 2020) and then us=, followed by a 5- or 6-digit number. What is this us identifier? Is it the microsecond (μs) part of the timestamp, or something else? I cannot find this in the documentation and cannot discern any pattern or meaning in the values.

score 0 · Accepted Answer · answered May 12 '20 at 09:23

Yes, it's the microseconds, you can see that in the code:

if (show_usec && tv.tv_usec)
{
    buf_printf(&out, " us=%ld", (long)tv.tv_usec);
}

https://github.com/OpenVPN/openvpn/blob/f57431cdc88f22fa4d7962946f0d3187fe058539/src/openvpn/otime.c#L133

 const bool show_usec = check_debug_level(DEBUG_LEVEL_USEC_TIME);

https://github.com/OpenVPN/openvpn/blob/948b4f938a02dee78fb5246bcd44bc0162619b2d/src/openvpn/error.c#L339

OpenVPN server log - what is the "us=" identifier following the timestamp?

1 Answers1