Change The RHEL/CentOS Linux Time Zone

-
After Linux server has been installed and you noticed that time zone has not been set correctly, here is how to do it:

1. Check the current time zone:

# cat /etc/sysconfig/clock
ZONE="America/New_York"

 # date
Thu Jul  9 06:46:14 EDT 2013


2. You can find the list of available time zones under /usr/share/zoneinfo:

# ls /usr/share/zoneinfo
Africa      Atlantic   Chile    Eire     Factory  GMT-0      Iceland      Jamaica    Mexico   NZ        posix       ROC        Universal  zone.tab
America     Australia  CST6CDT  EST      GB       GMT+0      Indian       Japan      Mideast  NZ-CHAT   posixrules  ROK        US         Zulu
Antarctica  Brazil     Cuba     EST5EDT  GB-Eire  Greenwich  Iran         Kwajalein  MST      Pacific   PRC         Singapore  UTC
Arctic      Canada     EET      Etc      GMT      Hongkong   iso3166.tab  Libya      MST7MDT  Poland    PST8PDT     Turkey     WET
Asia        CET        Egypt    Europe   GMT0     HST        Israel       MET        Navajo   Portugal  right       UCT        W-SU
# ls /usr/share/zoneinfo/Europe/
Amsterdam  Berlin      Chisinau    Helsinki     Kiev        Madrid     Moscow     Prague      Sarajevo    Tallinn   Vatican    Zagreb
Andorra    Bratislava  Copenhagen  Isle_of_Man  Lisbon      Malta      Nicosia    Riga        Simferopol  Tirane    Vienna     Zaporozhye
Athens     Brussels    Dublin      Istanbul     Ljubljana   Mariehamn  Oslo       Rome        Skopje      Tiraspol  Vilnius    Zurich
Belfast    Bucharest   Gibraltar   Jersey       London      Minsk      Paris      Samara      Sofia       Uzhgorod  Volgograd
Belgrade   Budapest    Guernsey    Kaliningrad  Luxembourg  Monaco     Podgorica  San_Marino  Stockholm   Vaduz     Warsaw


3. Change it to your desired time zone:

# vi /etc/sysconfig/clock

ZONE="Europe/Berlin"


4. Create a backup of current localtime file and create a new one as a symbolic link to the zone file:

# mv /etc/localtime /etc/localtime.old

# ln -sf /usr/share/zoneinfo/Europe/Berlin /etc/localtime

# ls -l /etc/localtime*


5. Time zone has been changed now:

# cat /etc/sysconfig/clock
ZONE="Europe/Berlin"

# date
Thu Jul  9 12:59:39 CEST 2013

But you can reboot the server in order for other applications running on the server use the new time zone. 





Comments

Post a comment

Popular posts from this blog

Running Docker Wildfly/JBoss Application Server in Debug mode via Eclipse

-
I have recently built the whole Development Environment of Java Enterprise Edition (J2EE) project on multiple Docker containers. It has saved the hassle of setting up a dev env for new developers. All it takes to setup the environment is to clone our github repositories and run the Docker images.

I will explain the setup in a future post.

Build Wildfly Docker Image with Debugging Enabled
So basically in order to run the Wildfly in debug mode, we need to add --debug flag to the Wildfly standalone.sh startup script.

Also we need to expose port 8787 in our image as it's the default port for Wildfly JVM debug mode.

1. Create or change your Wildfly Dockerfile as follows:
$ cat Dockerfile FROM jboss/wildfly:10.0.0.Final EXPOSE8787CMD["/opt/jboss/wildfly/bin/standalone.sh", "-b", "0.0.0.0", "-bmanagement", "0.0.0.0", "--debug"] 2. Build and tag the image:
$ docker build -t wildfly-debug . 3. Run the image either via  docker run:
$ …
Read more

Foreman fresh installation issue on Foreman proxy

-
After a fresh  installation of Foreman, I got another weird error while try to add a host to foreman:

# puppet agent --test
Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Failed when searching for node node.example.com: Failed to find node.example.com via exec: Execution of '/etc/puppet/node.rb node.example.com' returned 1:
Warning: Not using cache on failed catalog
Error: Could not retrieve catalog; skipping run


It turns out that issue is because of foreman proxy that it has not been created during installation.
So need to create it manually. In foreman GUI:
Infrastructure > Smart proxies > add new proxy
or if there is any exist edit it and correct the entry of your proxy FQDN. It's something like https://node.example.com:8443

And again, after try to add new proxy, yet another bug:  Unable to communicate with the proxy: ERF12-2530 [ProxyAPI::ProxyException]: Unable to detect features ([RestClient::RequestTimeout]: Request Timeout for proxy Plea…
Read more

Building RPM OpenSSH 7.1p1 on RHEL/CentOS 6.5

-
After I've implemented the OpenVAS vulnerability assessment system, I've made a complete vulnerability testing on the environment for both Linux and Wintel servers.

The result for the all Linux servers were Red :) Severity 10.0(High). The reason was the OpenSSH version 5.

Test result:

High (CVSS: 8.5)
NVT: OpenSSH Multiple Vulnerabilities (OID: 1.3.6.1.4.1.25623.1.0.806052) Product detection result: cpe:/a:openbsd:openssh:5.3 by SSH Server type and version (OID: 1.3.6.1.4.1.25623.1.0.10267) SummaryThis host is running OpenSSH and is prone to multiple vulnerabilities. Vulnerability Detection Result
Installed version: 5.3 Fixed version: 7.0 ImpactSuccessful exploitation will allow an attacker to gain privileges, to conduct impersonation attacks, to conduct brute-force attacks or cause a denial of service.
Impact Level: Application SolutionUpgrade to OpenSSH 7.0 or later. For updates refer to http://www.openssh.com Affected Software/OSOpenSSH versions before 7.0 Vulnerability InsightMu…
Read more