On Wed, December 10, 2014 17:51, Gordon Messmer wrote:

On 12/10/2014 12:47 PM, Dan Hyatt wrote:

...

I've a virtual instance and I need to know its IP address after it has finished booting up, to know where to ssh into it. I've tried adding "ip -4 addr > /dev/tty0" to rc.local, but that obviously doesn't work, because the login prompt overwrites everything I do.

The easy answer would be: don't fight the login prompt. "agetty" writes the contents of /etc/issue to the console before the login prompt. If /etc/issue contains "\4" then agetty will print the IPv4 address to the console.

See the man page for agetty, and update /etc/issue.

I find that CentOS-6 evidently does not support ; nor many of the /etc/issue flags defined in man 1 agetty:

/etc/issue CentOS release 6.6 (Final) Kernel \r on an \m

Test: b:\b d:\d s:\s l:\l m:\m n:\n o:\o O:\O r:\r t:\t u:\u 0:\0 4:\4 6:\6

login:

CentOS release 6.6 (Final) Kernel 2.6.32-504.1.3.el6.centos.plus.x86_64 on an x86_64

Test: b: d:09:19 on Thursday, 11 December 2014 s:Linux l:7 m:x86_64 n:vhost04.hamilton.harte-lyne.ca o: O: r:2.6.32-504.1.3.el6.centos.plus.x86_64 t:09:19 on Thursday, 11 December 2014 u: 0: 4: 6:

For ease in analysis (note that flags \0, \4, and \6 are not defined in agetty):

b: d:09:19 on Thursday, 11 December 2014 s:Linux l:7 m:x86_64 n:vhost04.hamilton.harte-lyne.ca o: O: r:2.6.32-504.1.3.el6.centos.plus.x86_64 t:09:19 on Thursday, 11 December 2014 u: 0: 4: 6:

Is there some configuration issue of which I am unaware? Where is the flag \4 usage defined?