Monday, May 30, 2016

Introducing Pipelight

Hi there!

I was trying to access a page with silverlight on it but I couldnt view the page correctly because I was using Mozilla and Linux. I need to instll silverlight plugin. I could've installed Project Mono but it has been discontinued the project and won't support it in the future. In Ubuntu forum, someone mentioned about Pipelight. The concept of Pipelight is running the plugin using wine (it will run in the background). It solved my problem. I can now access the page and view it correctly. Try it.

Have fun! :D

Wednesday, May 25, 2016

How to disable ctl+alt+backspace key from killing your X server in KDE?

I recently accidentally pressed ctrl+alt+backspace key combination. It killed my X server. To prevent it from happening again and to protect your unsaved works, you have to disable this key combination. For KDE 4.x users, below are the steps:

Open the settings page:
Menu --> Applications --> Settings --> System Settings

Open the Input Devices:

Clik on Keyboard and the Advanced tab and click on the Configure keyboard options checkbox:

Find Key sequence to kill the X server from the list and untick the check box for Ctrl + Alt + Backspace

And then click the Apply button to save the settings.

That is all there is to it. Have fun!

Thursday, May 19, 2016

Enable or disable a service from autostarting on ubuntu and derivatives

To make a upsmon service to autostart during bootup:

sudo update-rc.d upsmon enable

The output looks like this:

update-rc.d: warning: /etc/init.d/upsmon missing LSB information
update-rc.d: see
 Disabling system startup links for /etc/init.d/upsmon ...
 Removing any system startup links for /etc/init.d/upsmon ...
 Adding system startup for /etc/init.d/upsmon ...
   /etc/rc0.d/K06upsmon -> ../init.d/upsmon
   /etc/rc1.d/K06upsmon -> ../init.d/upsmon
   /etc/rc6.d/K06upsmon -> ../init.d/upsmon
   /etc/rc2.d/K39upsmon -> ../init.d/upsmon
   /etc/rc3.d/K39upsmon -> ../init.d/upsmon
   /etc/rc5.d/K39upsmon -> ../init.d/upsmon

To disable autostart:

sudo update-rc.d upsmon disable

The output:

update-rc.d: warning: /etc/init.d/upsmon missing LSB information
update-rc.d: see
 Enabling system startup links for /etc/init.d/upsmon ...
 Removing any system startup links for /etc/init.d/upsmon ...
 Adding system startup for /etc/init.d/upsmon ...
   /etc/rc0.d/K06upsmon -> ../init.d/upsmon
   /etc/rc1.d/K06upsmon -> ../init.d/upsmon
   /etc/rc6.d/K06upsmon -> ../init.d/upsmon
   /etc/rc2.d/S61upsmon -> ../init.d/upsmon
   /etc/rc3.d/S61upsmon -> ../init.d/upsmon
   /etc/rc5.d/S61upsmon -> ../init.d/upsmon

To see available services:

service --status-all

Monday, May 16, 2016

Installing thawte SSL cert in Zimbra 8.6.0

1. Create csr and keep your key file. Copy the key file to /opt/zimbra/ssl/zimbra/commercial/commercial.key
2. Give or upload your csr file to certificate provider
3. Get certificate given by your cert provider after your csr is accepted.
4. Get the root certificate of your provider. For thawte, mine is here
5. Get intermediate certificate. Mine is here
6. Combine the content of the root and intermediate cert files e.g cat intermediate.crt root.crt > commercial_ca.crt and copy it to dir /opt/zimbra/ssl/zimbra/commercial

Below is the steps to verify that the certificates are ok and ready to deploy. You can skip the first step if you have already create the csr.

Single-Node Commercial Certificate

We need to take care and ask for the Certificate authority for the Root and Intermediate Keys, we will need it soon.
We will use at least 2048-bit key, is the minimum for all Certificate Authorities: 1. Begin by generating a Certificate Signing Request (CSR).
/opt/zimbra/bin/zmcertmgr createcsr comm -new -subject "/C=US/ST=CA/L=Sunnyvale/O=Zimbra/OU=Zimbra Collaboration Suite/" -subjectAltNames
2. Next, submit the CSR to the SSL provider and get a commercial certificate in PEM format. Save the new certificate to a temporary file (e.g. /tmp/commercial.crt).
3. Now, download and save the root Certificate Authority (CA) from your provider to a temporary file. (e.g. /tmp/ca.crt)
4. Download any intermediary CAs from your provider to a temporary file. (e.g. /tmp/ca_intermediary.crt)
5. Combine root and intermediary CAs into a temporary file.
cat /tmp/ca_intermediary.crt /tmp/ca.crt > /tmp/ca_chain.crt
6. Verify your commercial certificate.
/opt/zimbra/bin/zmcertmgr verifycrt comm /opt/zimbra/ssl/zimbra/commercial/commercial.key /tmp/commercial.crt /tmp/ca_chain.crt
**Verifying /tmp/commercial.crt against
Certificate (/tmp/commercial.crt) and private key
(/opt/zimbra/ssl/zimbra/commercial/commercial.key) match.
Valid Certificate: /tmp/commercial.crt: OK
7. Deploy your commercial certificate.
/opt/zimbra/bin/zmcertmgr deploycrt comm /tmp/commercial.crt /tmp/ca_chain.crt
** Verifying /tmp/commercial.crt against
Certificate (/tmp/commercial.crt) and private key
(/opt/zimbra/ssl/zimbra/commercial/commercial.key) match.
Valid Certificate: /tmpt/commercial.crt: OK
**Copying commercial.crt to /opt/zimbra/ssl/zimbra/commercial/commercial.crt
**Appending CA chain /tmp/ca_chain.crt to
**Saving server config key zimbraSSLCeretificate…done.
**Saving server config key zimbraSSLPrivateKey…done.
**Installing mta certificate and key…done.
**Installing slapd certificate and key…done.
**Installing proxy certificate and key…done.
**Creating pkcs12 file /opt/zimbra/ssl/zimbra/jetty.pkcs12…done.
**Creating keystore file /opt/zimbra/mailbox/etc/keystore…done.
**Installing CA to /opt/zimbra/conf/ca…done.
If you get error "unable to get issuer certificate, please look at the steps in the link below.

Saturday, May 7, 2016

Changing display manager on Linux Mint using command

If you used to login to Linux using GUI, it means you were using X display manager. There are many display managers. Among popular ones are gdm, kdm, mdm and lightdm. You can change display manager using gui tools but you can also use command for that purpose. On Linux Mint (and i think on other debian-based distros), you can use this command (say you are using gdm):

dpkg-reconfigure gdm

A dialog will ask you whether you want to change to other installed display managers or not. You can replace mdm with other installed display manager.

That's all there is to it folk. Have fun! :D