Yum install from a local folder

cd <to your desired rpms location>

yum --disablerepo=* localinstall *.rpm

Linux File accessing via browser

Do following steps

1. cd /var/www/html

2. ln -s desired_directory linkName

3. chmod 755 Desired_Directory 

4. in /etc/httpd/conf/httpd.conf set as "UserDir disable"

How to change the hostname of machine

Follow either of following three steps

1. on shell prompt use command  hostname newname

2. in /etc/hosts mark entry against 127.0.0.0 newname

3. in /etc/sysconfig/network against HOSTNAME=newname 

the last one is permanent solution.

MAXIMUM POSSIBLE PACKET RATE ON A 10G LINK

One of the smallest packets commonly seen on networks is a TCP ACK. This has a 20 byte IP header and a 20 byte TCP header, adding up to 40 bytes. Because this is smaller than ethernet's minimum payload size of 46 bytes, it is automatically padded prior to transmission to bring it up to size. It is then wrapped with a 14 byte header and 4 byte CRC, to give the minimum ethernet frame size of 64 bytes.

When transmitted, each packet must also be preceded by a 7-byte preamble and 1-byte start-of-frame delimiter, and must be followed by an inter-frame gap of at least 12 bytes. This makes the smallest transmission in ethernet effectively 84 bytes.

We now have sufficient information to calculate the maximum packet rate on a 10G link:

10Gbps / (84 bytes * 8 bits) = 14.88Mpps

But the data rate that will be reported by most tools is significantly less, due to not counting the overheads:

14.88Mpps * 64 bytes * 8 bits = 7.62Gbps

Finally, we can work out the IP transmission efficiency (as opposed to ethernet efficiency) - it's pretty poor with such small packets:

14.88Mpps * 40 bytes * 8 bits / 10Gbps = 47.6%