Deleting Public Keys from GPG and RPM key rings

In order to delete the public keys from the key ring, we would require the key_id. The key_id can be idenfied using the below steps using the file where the public key is stored.

To get the Key Details

gpg --throw-keyids < [Key-File-Absolute Path]

pub  1021D/1689B887 2005-03-11 ABC Company 

sub  1048f/47E5X96D 2005-03-11  [expires: 2015-03-09]

To get the Key-ID from the keyfile

key_id=${gpg --throw-keyids < [Key-File-Absolute Path] | head -1 |  awk {'print $2'} |  cut -d '/' -f2 |  tr [A-Z] [a-z]}

1689B887

Delete from GPG keyring

gpg --delete-key  --yes $key_id

Delete from RPM keyring

rpm -e --allmatches gpg-pubkey-$key_id

Linux script to display tree structure of directory

ls -R | grep ":$" | sed -e 's/:$//' -e 's/[^-][^\/]*\//--/g' -e 's/^/   /' -e 's/-/|/'


Output from  a folder. This displays "ONLY" directories
 .
   |-resources
   |-src
   |---java
   |-target


(or)


yum install tree

tree -A
.
├── resources
├── src
│   ├── Hello.java
│   └── java
└── target

-A to be used if you use garbage chars as follows

.

âââ resources

âââ src

â   âââ Hello.java

â   âââ java

âââ target

Reference
http://ssteiner.wordpress.com/2009/05/12/quick-linux-tree-view-of-directory-contents/

Change Timezone in linux

Changing timezone in linux can be done using the below steps. Timezone is set using a symbolic link at /etc/localtime.


1. Check Date
     [root@vidhya-dev-vm1 ~]# date
     Tue Nov 20 14:23:51 IST 2012

2. To see how the current localtime is set
     [root@vidhya-dev-vm1 ~]# ll /etc/localtime

     lrwxrwxrwx. 1 root root 39 Nov 20 11:47 /etc/localtime -> /usr/share/zoneinfo/right/Asia/Calcutta

3. Check all the timezones
     [root@vidhya-dev-vm1 ~]# ls /usr/share/zoneinfo/
     Africa      Brazil   Egypt    GB         Hongkong     Jamaica    MST      Portugal    ROK        WET
     America     Canada   Eire     GB-Eire    HST          Japan      MST7MDT  posix       Singapore  W-SU
     Antarctica  CET      EST      GMT        Iceland      Kwajalein  Navajo   posixrules  Turkey     zone.tab
     Arctic      Chile    EST5EDT  GMT0       Indian       Libya      NZ       PRC         UCT        Zulu
     Asia        CST6CDT  Etc      GMT-0      Iran         MET        NZ-CHAT  PST8PDT     Universal
     Atlantic    Cuba     Europe   GMT+0      iso3166.tab  Mexico     Pacific  right       US
     Australia   EET      Factory  Greenwich  Israel       Mideast    Poland   ROC         UTC

4. Backup existing timezone and link new timezone

     [root@vidhya-dev-vm1 ~]# mv /etc/localtime /root/localtime_bak

     [root@vidhya-dev-vm1 ~]# ln -sf /usr/share/zoneinfo/America/Denver /etc/localtime

     [root@vidhya-dev-vm1 ~]# date

     Tue Nov 20 01:56:59 MST 2012