List all the files owned by a particular user or group

There are many commands used to find out files or directory as find which and locate.
But for searching for files owned by a specific user the command used is find.

“find” searches the directory tree rooted at each given file name by evaluating the given expression from left to right.

The format used by find command is

# find

If the path is not specified, then it will search in the current working directories.

In order to search files owns by a specific user you can use find command as

# find -user victoria

Here user is victoria.

In order to search files owns by a specific group you can use find command as

# find -group victoria

Increase the number of telnet sessions allowed :

The number of telnet sessions allowed is limited to 60 by default and it is controlled by xinetd. You can check it from /etc/xinetd.conf file on the server.
A default /etc/xinetd.conf file will be as per given below;

==================================
cat /etc/xinetd.conf
#
# Simple configuration file for xinetd
#
# Some defaults, and include /etc/xinetd.d/

defaults
{
instances               = 60
log_type                = SYSLOG authpriv
log_on_success          = HOST PID
log_on_failure          = HOST
cps                     = 25 30
}

includedir /etc/xinetd.d
==================================

In case you want to increase those sessions you will have to modify the line

instances               = 60

Put any number instaed of 60 say 100 and save the file.

instances               = 100

After any modification done in this file, you will have to restart the xinetd services.

# service xinetd restart

TCP -Transmission Control Protocol -It is a Protocol used in connection oriented networks

It breaks the data into packets and also supports error correction.

It supports error correction in the transmitted data and thus it is a reliable protocol. TCP is connection orinted protocol means it will get an acknoldgement for the packet it has forwarded.

It is synchronous in nature.

TCP-Not Used for real time applications. But it is used with applications such as web servers, Ftp uses TCP protocol.

It is bit slow compaire to UDP.

UDP - User Datagram Protocol - It is a protocol used in connectionless networks.

In UDP the data is transfered as packets. It also breaks the data into packets like the TCP, But it does not support error correction.

It does not support error correction in the transmitted data and it is not a reliable protocol like TCP.

It is asynchronous in nature.

UDP-Mostly used for real time applications. UDP is use for applications like video streaming and online gaming, where lost packets don’t need to be retransmitted.

It is more speedy than TCP.

Automatic way to fix RPM installations :

If you are installing rpm which is having many dependancies then you can do it with the up2date utility. It will automatically install all the dependencies for rpm package that is installed. If you have access to Red Hat Network (RHN) you can use the command up2date to update and it will download & install RPM packages.

>>>    up2date

It will connect to RHN (Red hat network), automatically download, and install the package.(Only for Registered channel). If there are dependencies or another RPM packages, they will be automatically get downloaded and installed as well.

For example:

# up2date smbfs-2.0.1-4       [programs to access SMB network servers]

The up2date command will automatically resolve, fetch and install any package dependencies for the package to be installed.

Also up2date command will download and install latest version of that package.

Setting up the Admin User for tomcat

Edit the “tomcat-users.xml” file as

vi /usr/local/jakarta/jakarta-tomcat-5.5.9/conf/tomcat-users.xml

[You will have to find out the path for tomcat-users.xml on your server first]

Add a line like in that conf file as :

 <user username=”username” password=”password” roles=”manager,admin”/>

You will have to check that none of the default users have the manager or admin roles.

Setting a Universal Co-ordinated Timezone

If your company is in country A; the data center is having timezone B; your customers are in country Y; and say their users are in country Z.

In this case you can  try Universal Co-ordinated Time (UTC).

Please edit the file /etc/sysconfig/clock as

vi /etc/sysconfig/clock

and change the UTC line as
“UTC=true”

You can set localtimezone to UTC as

ln -sf /usr/share/zoneinfo/UTC /etc/localtime

If you want to set your timezone other than UTC ,say your personal timezone, then you find that timezone under /usr/share/zoneinfo and link that to /etc/localtime as,

ln -sf /usr/share/zoneinfo/Country-name/City-name /etc/localtime.

PEAR Is short for ‘PHP Extension and Application Repository’

PEAR is having it’s primary goal to become a repository for PHP extensions and library code. The most important goal of the PEAR project is to try to define standard coding packages that can be used be developers directoly and it is re-usable coding.
Each package is a seperate project and is having a diffreent developer team.

Packages are in the gzipped tar files with a description file inside, and installed on your server using the PEAR installer.

You can install any pear package as
———–
pear install pear-package-name
———–

You can check all the PEAR packages that are available with
————
pear list-all
————

You can check installed PEAR packages on your server as
————
pear list
————

When you begin to look for a company to host your website, other than the amount of space and bandwidth that is offered, a company will usually promote the web hosting uptime they offer. Most web hosting companies like 1and1 , pickaweb, uk2.net offer an uptime guarantee to promote how well their service is. Other web hosting companies encourage their services by offering uptime assurance.

Web hosting uptime is a measurement of the time a computer server has been running, the longer the web hosting uptime the better the service (usually). Uptime is important to not only web hosting companies, but to any person or company that has a website, because if a website is down it could affect both your personal company’s reputation and goodwill of the web hosting uptime guarantee respectively. Web hosting companies strive for a 99.9% uptime, which means that there would be less than 2 minutes of downtime a day.

There are some factors that have huge impact on the uptime of a web provider, and rarely they are unavoidable. But good and reliable hosting companies try to prevent the downtime. Downtime is caused due to following reasons :
1) when the provider upgrades his server, or server is updated.
2) when some software companies put patch on the place of any fall foul of security.
3) when server is overloaded or any problem occurs in the performance of hardware or software or due to any nasty software.

Some temporary conclusions to resolve downtimes are:
1) Many web hosting companies provide friendly downtime message that will still allow the user know that the site is only temporarily down.
2) Larger web hosting companies are able to provide a quicker return to maintain their uptime guarantee, because they have staff readily available to respond to a downtime error quickly.
3) Smaller companies may experience a longer downtime. Because of lack of number of technical staff.

For reducing the risk of downtime, you can avoid purchasing the package from web host that has a lot of downtimes. You can go through forums and websites that keep the current record and reviews of almost all the hosting companies, where you can find their rating, their services and uptime they provide, and you can decide well before choosing any provider.
OR
You may choose webhost who cover the risk of downtime by compensating you with (1-Month Free Web Hosting added to your account) if ever you face downtime of (90+ minutes in total)monthly. Or credit the amount of downtime to your next month’s hosting fees.

In order to receive your web hosting service credit you must:

a) Email the details of the downtime to their support department
b) And as soon as your downtime is verified, your account will be addded with 1month free hosting or adjustment of hosting fees in the next month.

But if you have already hosted your site and you are facing the problem of large downtimes, you can contact to technical support or to any customer service unit. They will check and give you information that when your site will be restored. Many other web hosting companies provide with the compensation But make it clear that not a single company provides 100% uptime guarantee and if you are facing great downtime problems then the only way is you can transfer your site to some other established and reliable company.

So, go ahead and choose a Reliable webhost.