Cyrus Simple Authentication and Security Layer (SASL) library authenticates a remote SMTP client’s username and password; while the email accounts are part of the local system accounts. To enable (SASL) authentication in Postfix SMTP server follow these steps:
Step 1: Verify that cyrus-sasl has been installed.
Step 2: Modify /etc/postfix/main.cf, adding the following two lines.
smtpd_sasl_path = smtpd smtpd_sasl_auth_enable = yes
Step 3: Modify /usr/lib/sasl2/smtpd.conf
pwcheck_method: saslauthd mech_list: PLAIN LOGIN
Step 4: Start the postfix and saslauthd service
service saslauthd start service postfix start
Step 5: Test the SASL authentication on the Postfix SMTP server. To test the server side, connect to the Postfix SMTP server port to demonstrate if the connection is successful.
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The processor must support Hardware-Assisted Virtual Machine (HVM).
To check if the processor supports HVM use the following command:
grep -i vmx /proc/cpuinfo
grep -i svm /proc/cpuinfo
How can I list the currently active clients?
The winbindd deamon can log its status to the winbind log file upon request using the signal USR2.
If debuglevel is set to 2 or above, the windbindd dameon will also print the list of clients currently active.
# killall -USR2 winbindd
The winbind log level can be set separately in the smb.conf (/etc/samba/smb.conf) file using the "log level" option, for example:
log level = 2 winbind:3
Note: Reload the configuration in winbind by either sending a HUP signal to the winbindd daemon or by using "service winbind reload":
# service winbind reload
The suspend/hibernate menu entries in the "System" menu of the Gnome panel are linked to the Gnome Power Manager. If the Gnome Power Manager supports "suspend" or "hibernate", then the corresponding options will show in the menu.
To remove the "Suspend" or "Hibernate" options from the Gnome System menu,instruct the Gnome Power Manager to disable support for suspend and/or hibernate.
This can be achieved either graphically using gconf-editor by browsing to apps/gnome-power-manager and unset the options "can_hibernate" and "can_suspend", or use the command line tool gconftool-2:
$ gconftool-2 --type boolean --set /apps/gnome-power-manager/can_suspend false $ gconftool-2 --type boolean --set /apps/gnome-power-manager/can_hibernate false
This sets the option for the current user. To set this by default for all users, you can use the following commands as root:
# gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --type boolean --set /apps/gnome-power-manager/can_hibernate false # gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --type boolean --set /apps/gnome-power-manager/can_suspend false
To find the label of a partition, use this command:
# blkid -s LABEL /dev/<partition>
Replace <partition> with the name of the swap partition.
This command will also work with any other type of partition
No, the fence_apc script requires that the admin user (typically called apc) be used for fencing. Regular users have a different menu interface than the admin user and the fencing agent is incompatible with this interface.
To avoid exposing the admin password in the cluster configuration file, a password script can be used. This script needs execute permissions for root only preventing others from reading or executing it. The script can be as simple as:
#!/bin/bash echo "mypassword"
Once it is in place, use system-config-cluster or Conga to edit the fence device properties. There is an option to specify a password script instead of the clear text password.
If a script that has been written needs to be run as a particular user, the /etc/sudoers file needs to be modified to include default user options.
Edit the /etc/sudoers file by invoking:
#visudo
In this example, SCRIPT1 is the script that will be executed. TESTUSER is the alias of users who have permission to execute the script via sudo and test is the user that the script must be run as.
Cmnd_Alias SCRIPT1=/bin/blah.sh User_Alias TESTUSER=test,test1,test2 Defaults:TESTUSER runas_default=test TESTUSER ALL=NOPASSWD: SCRIPT1
If the sudo /bin/blah.sh command is invoked by the test, test1, or test2 users it will run as user test.
This Red Hat Knowledgebase article applies to Red Hat® Enterprise Linux® versions 4 and 5.
Microsoft® Windows® Vista Service Pack 1 (SP1) introduced additional authentication principals and differences in the methods used to encode and decode packets between peers as default behavior. The result is that Windows Vista clients cannot properly authenticate or access shares on Samba servers of versions prior to 3.0.28 once SP1 has been installed.
Red Hat Enterprise Linux version 4 Update 7 and version 5 Update 2 will include Samba version 3.0.28, which addresses these interoperability issues and others seen with prior Samba versions.
Red Hat Enterprise Linux 4 and 5 customers experiencing significant impact to their operations involving Samba servers and Windows Vista clients after installation of Windows Vista SP1 are encouraged to contact Red Hat Global Support if a solution is required before the next update release. » Read more
