Tag: redhat

Getting IP address after installing CentOS / Red Hat Linux in a virtual machine

I installed a VirtualBox/Parallels Desktop virtual machine with CentOS 6 and it didn’t automatically set up the network card with DHCP. I needed to add the following configuration to the file

root@centos:/etc/sysconfig/network-scripts # vi ifcfg-eth0
DEVICE=”eth0″
HWADDR=”00:1C:42:C0:FF:EE”
NM_CONTROLLED=”yes”
ONBOOT=”yes”
BOOTPROTO=”dhcp”

Then restart the network service

root@centos:/etc/sysconfig/network-scripts # service network restart
Shutting down interface eth0: [ OK ]
Shutting down loopback interface: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0:
Determining IP information for eth0… done.
[ OK ]

Fencing agent ipmi_ilo incompatible with Red Hat Cluster and HP iLO3

I have a two node Red Hat Cluster with HP Proliant servers.

This server has an HP iLO3 for Out-of-band management.

The fence_ilo agent works with iLO and iLO2.
Fence Device and Agent Information for Red Hat Enterprise Linux

You will need to use fence_ipmplan agent with the recommended settings following this Red Hat document:
How do you configure the fence device agent information option for the HP ILO 3?

Linux denying user access after reseting password

Depending of how you configured your Linux server, the Pluggable Authentication Module (PAM) won’t let you login.

To check the login attempts to see if it needs to be reset type faillog -u <username>

root@linux:~ # faillog -u username
Username Failures Maximum Latest
<username>       15        0

Reset the counter with the -r flag

root@linux:~ # /usr/bin/faillog -r username
Username Failures Maximum Latest
<username>        0        0

If you’re root but is not managing to become a user with su, you also need to reset the login counter

root@linuxserver ~ # su – username
su: incorrect password

root@linux:~ # /sbin/pam_tally —-user username —-reset
User <username> (685) had 36

root@linux:~ # su – username
username@linux:~ $

For RHEL 6, it uses pam_tally2

root@rhel64:~ # /sbin/pam_tally2 —-user username —-reset
Login Failures Latest failure From
username 9 02/13/14 09:22:10 /dev/pts/1

root@rhel64:~ # /sbin/pam_tally2 —-user username —-reset
Login Failures Latest failure From
username 0