Since this is more of a hosting blog, I’ll focus on banning an IP address. There are few ways to do it. First of all, you have to identify the IP address. Be very careful about this. If you ban your own IP will not be able to login to undo it! Or sometimes a client could be using a service or software to monitor your site. Don’t be too quick to identify it as a ‘hack attempt’… In my case, I’m sure of the site scrapping my content. I ping-ed the site and also cross-checked with the logs to confirm the offending IP.

If you’re running IP tables, you can SSH in and run the following:

iptables -A INPUT -s -j DROP

The other alternative is to block and IP in Plesk (I’m using Plesk 9.x)

1. Login as ‘admin’.
2. Go to Settings > Manage Firewall Rules
3. Click on Edit Firewall Configuration
4. Click on Add Custom Rule
5. Give the rule a name and change the settings as per the image below:

Its even easier in cPanel. When you login, look under the “Security” grouping and locate the “IP Deny Manager” icon. In the next window just add your IP and submit. Can’t go wrong with that! Just be careful not to enter ‘wildcard’ IPs like 202.*.*.* which means all IPs starting with 202 will be blocked.

So, there you go. A simple tutorial that will save you time (and bandwidth is someone is hotlinking your images or videos). Please leave a comment below if you have other favorite techniques or tips that you’d like to share.

Post from: www.vpsguides.com - Guides, Tutorials, Tips and Articles on Everything VPS!

How To Ban An IP Address

One of the major task was to migrate email accounts from our legacy VPS running FreeBSD 4.7 to newer ones running 6.3. Here’s how I did it.

1. Copied the passwords from /etc/passwd in the older 4.7 servers.
   (Copy the part right after the name until right before the colon – e.g. mike:54YBKHNIE0.3L: ) UPDATE: Someone suggested a utility called ‘vipw’. Haven’t tried it yet.
2. Pasted them into /etc/master.passwd of new server.
   (Create the users you need first with any temp password. The paste the one above between the name and colon)
3. Ran pwd_mkdb -p /etc/master.passwd
4. Updated the MX and A record for the mail server to point to the new server. We normally migrate email and web separately to minimise downtime. Using a good DNS service like DNS Made Easy allows you to set a low TTL for these changes to take affect quickly.
5. Finally, I commented out the hostname in /etc/hosts on the old server to tell it that it no longer manages emails for this domain.
6. Finally finally, I forwarded old emails using Mutt to the new account.

Hope this helps, worked wonders for us. Clients had no disruption to their emails which meant little grief for me!

Post from: www.vpsguides.com - Guides, Tutorials, Tips and Articles on Everything VPS!

Migrating Email Accounts on FreeBSD

As a freelance Linux consultant, many of my clients are often interested in making their VPS (Virtual Private Server) as responsive as possible. Since VPS servers by nature have somewhat limited system resources (often less than 1 GB of RAM), getting the best VPS performance can be a crucial part of running a successful server. To make matters worse, most clients assume that the VPS host has already optimized their server- which simply isn’t true (even Rackspace, a wonderful VPS host, doesn’t do this). Therefore, I’ve written this article as a brief introduction to some of the more common ways to get the best performance from a VPS.

Tip #1: Disable system services.
The top way to increase your VPS performance is to disable any system services that are not necessary. Services that are never used will still use up valuable RAM and CPU time, and also possibly allow your server to be attacked remotely. If you don’t need these services, why have them? Manage the startup scripts that start these services at boot time, and disable them.

Tip #2: Configure MySQL properly.
One of the more common ways to increase the available RAM (or to allocate more RAM to MySQL) is to configure the MySQL cache sizes. If your MySQL server instance is using too much memory, decrease the cache sizes. Likewise, if MySQL gets bogged down with large requests, increase the MySQL cache.

Tip #3: Configure Apache properly.
With Apache 2.0, many system administrators and clients alike have become confused as to the proper configuration of the Apache worker threads. Check how much memory Apache is using, and adjust the StartServers and MinSpareServers directives as needed to free up more memory.

Tip #4: Clean up your modules!
Without exception, there will always be modules or features that are enabled in memory hungry server software packages (such as Apache) that simply are not needed. Take a look at the configuration files for Apache, and decide if you need FrontPage support, or some of the other extra modules that ship with the VPS software packages. Disabling unnecessary modules or plugins will decrease the system memory that server software such as Apache requires, which will give you more resources for the software that needs it!

Tip #5: Disable control panels.
Let’s face it, everyone loves the more popular control panels, such as Cpanel, Plesk, Webmin, and phpMyAdmin. Heck, I’ve even written tutorials on how to use some of these control panel software packages. However, disabling these software packages frees up quite a bit of resources- sometimes as much as 120 MB of RAM! Sometimes the best solution is to disable these control panels until you actually need them- then they can be turned on via a PHP script (albeit somewhat insecure), or via a command entered at a shell prompt.

These 5 tips should decease the amount of RAM that your VPS uses by as much as 30-40%, which might save you quite a bit of money per month. Since most providers start out their VPS plans at systems with 256MB of RAM (and upgrades from there are expensive, often costing $40/month for an additional 256 MB), optimization of a VPS server is a crucial step. In addition, these 5 tips can be performed by a talented system administrator or consultant in typically less than two hours, which can mean a return on investment after only two or three billing cycles. What you do with the extra money saved is your business- you’ve earned it!

Christopher J. Pace is a freelance Linux consultant who has worked with Linux since 2001. Currently, he provides remote Linux consulting services for sick servers.

Post from: www.vpsguides.com - Guides, Tutorials, Tips and Articles on Everything VPS!

5 Linux VPS Performance Tips