lost and found ( for me ? ): October 2015

Reference

http://blog.chrysocome.net/2013/05/proliant-virtual-serial-port.html

http://balazsdeak.blogspot.jp/2015/02/hp-dl380-serial-console-with-red-hat.html

OS : CentOS 6.7

iLO 4

BIOS settings ( default settings )

Set ‘BIOS Serial Console Port’ to COM2
Set ‘BIOS Serial Console Baud Rate’ to 115200

When ttyS1(ttyS1 is for COM2) is not configured on your OS, you will see nothing when connecting to VSP as below.

Access to an iLO over SSH and enter VSP.

$ ssh 192.168.10.10 -l user

</>hpiLO-> VSP

Virtual Serial Port Active: COM2

Starting virtual serial port.

Press 'ESC (' to return to the CLI Session.

*** blank ***

</>hpiLO->

Configure ttyS1.

Create a file named “ttyS1.conf” under /etc/init directory.

$ sudo vi /etc/init/ttyS1.conf

$ sudo cat /etc/init/ttyS1.conf

stop on runlevel [S016]

start on runlevel [235]

respawn

instance /dev/ttyS1

exec /sbin/agetty 115200 ttyS1 vt100

Add ttyS1 in securetty file.

$ sudo tail -1 /etc/securetty

ttyS1

enable ttyS1.

$ sudo initctl start ttyS1

ttyS1 (/dev/ttyS1) start/running, process 8406

Access to the VSP over SSH.

</>hpiLO-> VSP

Virtual Serial Port Active: COM2

Starting virtual serial port.

Press 'ESC (' to return to the CLI Session.

localhost.localdomain login:

CentOS release 6.7 (Final)

Kernel 2.6.32-573.7.1.el6.x86_64 on an x86_64

In CentOS6, init daemon uses upstart, not Sys V init, so ‘telinit q’ does not work.

You need to create a file under /etc/init directory instead of editing /etc/inittab file.

edit /etc/grub.conf so that you can see boot messages.

timeout=5

# unit=0 for COM1, unit=1 for COM2

serial --unit=1 --speed=115200 --word=8 --parity=no --stop=1

terminal --timeout=5 serial console

#splashimage=(hd0,1)/grub/splash.xpm.gz

hiddenmenu

title CentOS (2.6.32-573.7.1.el6.x86_64)

root (hd0,1)

kernel /boot/vmlinuz-2.6.32-573.7.1.el6.x86_64 ro root=UUID=aaa rd_NO_LUKS rd_NO_MD crashkernel=auto rhgb quiet console=tty0 consle=ttyS1,115200n8

hattori@ubuntu:~$ tail -1 /etc/lsb-release

DISTRIB_DESCRIPTION="Ubuntu 14.04.3 LTS"

hattori@ubuntu:~$

hattori@ubuntu:~$ dnsmasq --version

By adding MAC address in DNS queries, DNS servers could identify devices even though those devices are behind NAT environment by looking at MAC address in DNS queries. ( If DNS servers can recognize that. )

dnsmasq can add MAC address in DNS queries in EDNS0.

man dnsmasq

--add-mac

Add the MAC address of the requestor to DNS queries which are

forwarded upstream. This may be used to DNS filtering by the

upstream server. The MAC address can only be added if the

requestor is on the same subnet as the dnsmasq server. Note that

the mechanism used to achieve this (an EDNS0 option) is not yet

standardised, so this should be considered experimental. Also

note that exposing MAC addresses in this way may have security

and privacy implications. The warning about caching given for

--add-subnet applies to --add-mac too.

By default, dnsmasq does not add MAC address in DNS queries.

dnsmasq configuration file for LXC(lxc-net) is /etc/init/lxc-net.conf.

So I modified that so that dnsmasq can add MAC address into DNS queries.

Copy a current config file.

hattori@ubuntu:~$ sudo cp /etc/init/lxc-net.conf ./lxc-net.conf.20151024

Edit lxc-net.conf.

Add '--add-mac' option in that file.

$ diff /etc/init/lxc-net.conf lxc-net.conf.20151024

65c65

< dnsmasq $LXC_DOMAIN_ARG -u lxc-dnsmasq --strict-order --bind-interfaces --pid-file=${varrun}/dnsmasq.pid --conf-file=${LXC_DHCP_CONFILE} --listen-address ${LXC_ADDR} --dhcp-range ${LXC_DHCP_RANGE} --dhcp-lease-max=${LXC_DHCP_MAX} --dhcp-no-override --except-interface=lo --interface=${LXC_BRIDGE} --dhcp-leasefile=/var/lib/misc/dnsmasq.${LXC_BRIDGE}.leases --dhcp-authoritative --add-mac || cleanup

---

> dnsmasq $LXC_DOMAIN_ARG -u lxc-dnsmasq --strict-order --bind-interfaces --pid-file=${varrun}/dnsmasq.pid --conf-file=${LXC_DHCP_CONFILE} --listen-address ${LXC_ADDR} --dhcp-range ${LXC_DHCP_RANGE} --dhcp-lease-max=${LXC_DHCP_MAX} --dhcp-no-override --except-interface=lo --interface=${LXC_BRIDGE} --dhcp-leasefile=/var/lib/misc/dnsmasq.${LXC_BRIDGE}.leases --dhcp-authoritative || cleanup

stop and start lxc-net to reflect that change.

check current PID of dnsmasq.

hattori@ubuntu:~$ cat /var/run/lxc/dnsmasq.pid

1480

Here are current options.

hattori@ubuntu:~$ ps aux | grep 1480 | grep -v grep

lxc-dns+ 1480 0.0 0.0 28204 968 ? S 10月23 0:00 dnsmasq -u lxc-dnsmasq --strict-order --bind-interfaces --pid-file=/run/lxc/dnsmasq.pid --conf-file= --listen-address 10.0.3.1 --dhcp-range 10.0.3.2,10.0.3.254 --dhcp-lease-max=253 --dhcp-no-override --except-interface=lo --interface=lxcbr0 --dhcp-leasefile=/var/lib/misc/dnsmasq.lxcbr0.leases --dhcp-authoritative

root 1533 0.0 0.0 450312 14808 ? Sl 10月23 0:00 /usr/sbin/libvirtd -d

stop and start lxc-net.

hattori@ubuntu:~$ sudo stop lxc-net

lxc-net stop/waiting

hattori@ubuntu:~$ sudo start lxc-net

lxc-net start/running

hattori@ubuntu:~$ cat /var/run/lxc/dnsmasq.pid

6558

dnsmasq has started with --add-mac option.

hattori@ubuntu:~$ ps aux | grep 6558 | grep -v grep

lxc-dns+ 6558 0.0 0.0 28204 960 ? S 00:59 0:00 dnsmasq -u lxc-dnsmasq --strict-order --bind-interfaces --pid-file=/run/lxc/dnsmasq.pid --conf-file= --listen-address 10.0.3.1 --dhcp-range 10.0.3.2,10.0.3.254 --dhcp-lease-max=253 --dhcp-no-override --except-interface=lo --interface=lxcbr0 --dhcp-leasefile=/var/lib/misc/dnsmasq.lxcbr0.leases --dhcp-authoritative --add-mac

Start a container.

hattori@ubuntu:~$ sudo lxc-start -n ubuntu01 -d

Connect to the container and check MAC address of that container.

hattori@ubuntu:~$ sudo lxc-ls -f

NAME STATE IPV4 IPV6 AUTOSTART

----------------------------------------------------

ubuntu-original STOPPED - - NO

ubuntu01 RUNNING 10.0.3.47 - NO

ubuntu02 STOPPED - - NO

ubuntu03 STOPPED - - NO

ubuntu04 STOPPED - - NO

hattori@ubuntu:~$

hattori@ubuntu:~$ ssh 10.0.3.47 -l ubuntu

ubuntu@10.0.3.47's password:

Welcome to Ubuntu 14.04.3 LTS (GNU/Linux 3.13.0-66-generic x86_64)

* Documentation: https://help.ubuntu.com/

Last login: Sat Oct 24 00:26:17 2015 from 10.0.3.1

ubuntu@ubuntu01:~$

Here is a resolv.conf of the container.

This container sends DNS queries to dnsmasq(10.0.3.1).

root@ubuntu01:~# cat /etc/resolv.conf

# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)

# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN

nameserver 10.0.3.1

root@ubuntu01:~#

Here is a MAC address of the container.

root@ubuntu01:~# ip addr show eth0 | grep 'link/ether'

link/ether 00:16:3e:09:dc:c2 brd ff:ff:ff:ff:ff:ff

Here is a capture data collected on LXC host when dnsmasq sent DNS queries to other DNS servers.

Having looked at the capture data, you can see MAC address in DNS queries which was added by dnsmasq.

Queries

www.google.com: type A, class IN

Name: www.google.com

Type: A (Host address)

Class: IN (0x0001)

Additional records

<Root>: type OPT

Name: <Root>

Type: OPT (EDNS0 option)

UDP payload size: 4096

Higher bits in extended RCODE: 0x0

EDNS0 version: 0

Z: 0x0

Data length: 10

Option: Unknown (65001)

Option Code: Unknown (65001)

Option Length: 6

Option Data: 00163e09dcc2

lost and found ( for me ? )

lost and found ( for me ? )

iLO4 : access to an iLO VSP(virtual serial port) over SSH

LXC, dnsmasq : How to configure dnsmasq to have dnsmasq add MAC address of containers when dnsmasq sends DNS queries to other DNS servers.