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UEFI and Ubuntu

https://help.ubuntu.com/community/UEFI

http://askubuntu.com/questions/221835/installing-ubuntu-on-a-pre-installed-uefi-supported-windows-8-system

Sendmail smtp auth under CentOS 6

1.Get signed server certificate for auth

2. edit sendmail.mc as below : (port 587 is listened by default, no need to add in the mc)

define(`confAUTH_OPTIONS’, `A p y’)dnl TRUST_AUTH_MECH(`LOGIN PLAIN’)dnl define(`confAUTH_MECHANISMS’, `LOGIN PLAIN’)dnl define(`confCACERT_PATH’,`/etc/pki/tls/certs’) define(`confCACERT’,`/etc/pki/tls/certs/gd_bundle.crt’) define(`confSERVER_CERT’,`/etc/pki/tls/certs/server.crt’) define(`confSERVER_KEY’,`/etc/pki/tls/certs/server.key’) DAEMON_OPTIONS(`Port=465,Addr=0.0.0.0, Name=MTA’)

3. install saslauthd, make sure the below are installed :

cyrus-sasl-plain cyrus-sasl-devel cyrus-sasl-lib […]

Use NOOP I/O Scheduler for virtualized Linux guest with kernel 2.6 guest on vmware

Refer to http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2011861

The scheduler can be set for each hard disk unit. To check which scheduler is being used for particular drive, run this command:

cat /sys/block/disk/queue/scheduler

For example, to check the current I/O scheduler for sda:

# cat /sys/block/sda/queue/scheduler [noop] anticipatory deadline cfq

In this example, the sda drive scheduler is set to […]

Linux 2.6+ tuning for Data Transfer hosts connected at speeds of 1Gbps or higher

http://fasterdata.es.net/host-tuning/linux/

Nagios nrep “NRPE: Unable to read output” after using sudo

edit /etc/sudoers and comment the below :

#Defaults requiretty

Windows 7 autologin

Use netplwiz

Enhanced vMotion Compatibility (EVC) with creating a cluster or the required license

http://admin-reminder.blogspot.hk/2011/11/vmware-cpuid-masks-for-aes-ni-and.html

In short

Edit CPUID Mask in vsphere at “Level 1 section” and for “ecx” :

—- –0- —- —- —- —- —- –0-

Linux iptables firewall rules to prevent private IP leakage from masquerade/SNAT

Unroutable TCP type packets, from reserved for local use only networks (RFC1918), being sent out to internet on a Linux masquerade box.

See http://www.smythies.com/~doug/network/iptables_notes/index.html

And http://en.wikipedia.org/wiki/Transmission_Control_Protocol#Connection_termination

The User Profile Service service failed the logon. User profile cannot be loaded.

Sign into another Windows account. Run the registry editor. Navigate to HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList. Look at the sub-keys here in the form of S-1-5-21-XXXXXXXXXX-XXXXXXXXXX-XXXXXXXXXX-XXXX. One of them is probably duplicated with the extension “.bak.” Remove (or backup) the one without the .bak, and then rename the remaining one, removing the .bak extension.

I run the […]