I have shut down my linux web server using ssh command <pre class="prettyprint"><code> ~# shutdown -h now </code></pre> how can i restart the server again. i am trying out different things but they are not helping. How to restart using ssh.

<code>reboot</code> or if you want to restart just apache then <code>/etc/init.d/apache2 restart</code> and if you want to shutdown then instead of <code>shutdown -h now</code> you can simply use <code>poweroff</code>

You have powered off the machine, you can't restart it from SSH. unless it supports Wake from Lan. If you want to only restart your web server use <code>apachectl restart</code>