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Web Hosting - Managing Disk Space
Few things are less exciting than managing the disk space that always seems to be in too short a supply. But few things are more important to the health and well being of your site.
The most obvious aspect of managing disk space is the need to have enough. If you have only a few dozen web pages, that's not an issue. But as the amount of information (web pages, database content and more) grows, the quantity of free space goes down.
That's important for two reasons.
All permanent information on a computer is stored on hard drives. Temporary information is often stored in memory only. The two components are completely separate, though they are sometimes confused with one another. As the amount of free space on the hard drive decreases several effects occur.
Here's one way to picture them...
Imagine you had a table with a certain area and you lay out playing cards on the table. At first, you lay them out in order, the 2 at the side of the 3, then 4, and so on. But then you pick up one or two cards from the middle and discard them. Then you add some more cards. Pretty soon things look pretty random.
Now cover the cards with a big opaque sheet of paper.
You want the cards to appear in order when displayed to someone. A special robot could be designed to always pick up the cards from underneath the sheet in order. Or, it could slide a hole in the sheet over the cards to display them in the correct order (2, 3, 4, ...), no matter what order they are really in. That's similar to how the operating system always shows you information in a sensible way, even though it's actually stored randomly.
Why should you care?
Real files are stored in pieces scattered around the drive wherever there is space for them. The more free space there is, the quicker the operating system can find a place to store a new piece. That means, if you delete the junk you no longer need (and free up more space) the system actually runs quicker. It helps create space you might need, and allows the operating system to store files for you faster.
But there's a second effect.
As you delete old files or change them, the pieces get more and more scattered. It takes the 'robot' longer and longer to fetch or display the 'cards' in order. Existing files are fetched and put together 'on the fly' (say, when you request a graphical page or a list of names). But, it takes longer to put together the web page when there are more scattered pieces.
So, the other aspect of managing disk space is to keep the pieces of the files more or less in order. A utility that does that is called a 'de-fragger' or de-fragmentation program. You can request that a system administrator run it, or if you have the authority, you can run it yourself. That keeps the 'cards' in order and allows for quicker access to them.
So, managing disk space involves chiefly three things: (1) keeping enough space to store what you need to store, and also (2) keeping enough free space to make new file storage quick and (3) making old file retrieval fast by keeping things orderly.
When only a few files are involved the benefit isn't worth the effort. But as the number and size of the files grow, to thousands of files or several gigabytes of data, the effect becomes more noticeable. Keeping things organized then makes a significant difference in performance.
Much of this can be automated using utilities. Some will delete files in a certain folder older than a certain date. A de-fragger can be set to run automatically during times of light usage, or quietly in the background at all times. Discuss the options with your system administrator and help him or her do the job better by keeping your house in order. You'll benefit by having a better performing web site.
Web Hosting - Domain Name Changes and How They Affect You New domain names are registered all the time, and ones previously registered expired. Sometimes that's the result of simple neglect. The owner of the name chose not to renew his or her ownership, so the name became available for someone else to use. In rare cases, a highly original mind managed to think of a new one. In the other common scenarios, someone chose to just let it go or sell it. When you choose to change your domain name, there are actually two separate steps involved: releasing the old name, and adopting the new one. But, just as the postal system can have difficulty forwarding your letters when you change your personal name, changing your domain name brings certain difficulties. One of the most prominent is the fact that any name change requires a change to thousands of DNS Servers around the globe. DNS (Domain Name System) is the set of software/hardware components that allows domain names to map to IP addresses. IP addresses are what are actually used 'under the covers' when one computer communicates with another. Note that there isn't always a 1:1 correspondence between a name and an IP address. One IP address can serve multiple domain names and one domain name can have multiple IP addresses. For the sake of simplicity, we'll stick to the common case here. DNS servers around the world maintain internal databases that match the name to an IP address. Not all servers have all pairs of names/addresses. A series of complex routines allows a request to be forwarded when the particular DNS server doesn't have a needed record. When you acquire a domain name that used to be associated with a given IP address, the odds of you acquiring the same IP address are extremely low. In the unlikely case, for example, that you acquired the domain name yahoo.com, you would almost certainly not get the IP address that was matched with it (unless you bought the Yahoo! company). So, as a result of the change, the name/IP address pair is no longer what it was. A similar circumstance exists when you retain your IP address, but want to change the domain name associated with it. In either case, the pairing has changed. The catch is this: when the change takes place, those DNS databases are not all updated instantaneously around the world. Even apart from the limited speed with which computers and networks operate, (and neglecting the human factor if/when the change is made manually to more than one server) the reason is something called caching. In order to communicate efficiently, DNS servers are designed to assume that changes will be relatively rare. Just as with the postal system, you don't move your address or change your name every minute. Since that's true, in general, the name/IP address pair is cached. A cache is a set of stored information that is reused so that fresh information doesn't have to be communicated with every request for a web page or data. A chain of DNS servers pass requests to the last known address. There is usually more than one system between your computer and the server you want to communicate with. Most of the time, that's your current name/address. When you change the name, that pair is no longer valid. In order to propagate the new name/address pair (so the terminology goes), that cache has to be refreshed. Something similar happens when you establish an entirely new name. That name is first associated with an IP address and that pair has to be communicated to DNS servers around the world in order for you to be able to reach any one of them at random. But DNS servers don't do that until they are requested to do so by your action of asking for information from a remote server. Because of that, but chiefly because of caching, it can take quite a while for the new pair to become known around the Internet. Caches can expire and get refreshed in a few minutes or a few hours. It varies. That time can be as short as an hour or less, if the path between your computer and the web server is very simple and only one DNS server needs to be updated. Or, it can take up to 48 hours or more. Though the 'official' range is often given by registrars as 24-48 hours, the average is closer to about six hours. But that's an average. The actual time in any given case can (and does) vary widely. In the meantime, a number of effects can occur. The most obvious is that, since the name/IP address pair can't be resolved properly, you don't reach the server you want. Your browser points to the old one (in the rare case it's still accessible by that name and address), or it simply reports there's no such name at that address. So, when registering a new name or buying an old one, you should establish the site, but not advertise it for at least a couple of days. Better to wait to get visitors than to turn them off by being 'not at home' when they call.
Web Hosting - Do It Yourself Administration, Things to Consider The choice of whether or not to try to administer your own web site brings with it a host, pun intended, of issues. For most web site owners, the primary focus is naturally on creating, maintaining and enhancing the site. That often is just part of managing an entire business, for which the web site is just the means to an end. That implies there will be little interest in or time left over for technical administration like database maintenance (tuning, space management, security, bug fixes), establishing and maintaining backups to ensure they're successful and usable, email administration, disk space management, applying operating system fixes for bugs and security, and other tasks. But cost is always a factor in any business. Paying for technical help can burden the budget of a new and struggling business. Consulting fees can range from a few dollars an hour to over $100. On the lower end, the poor skill level and quality of work will make it not worth even that small amount. On the higher end, you can quickly rack up expenses that will bust your business. Permanent employees are usually somewhere in the middle of that range when you add up salary, employment taxes and more. Often, server and/or web site administration can be paid for as part of the web hosting package. That cost is usually lower than independent contracting help, but those staff are usually tasked with maintaining dozens if not hundreds of servers and sites. They can, therefore, give very little individual attention to yours. Often, novice web site owners are intimidated by some of the technical requirements for server or site administration. But, as with anything, a little familiarity can show that the knowledge required is more modest than one might expect. Administration in many cases involves fairly elementary, and frequently repetitive, tasks. These can be learned easily. Using a test site or a free hosting service is a good way to practice and learn without risk or cost, other than time invested. Once that initial hurdle is jumped over, administration can be done quickly and some even find it interesting. It allows the site owner to exercise additional control over the total product, and there's satisfaction in being able to say 'I did that' even if you prefer not to do it forever. That real-life learning experience also allows the site owner to better judge any consultants or staff that are hired. It's much easier to judge if someone is providing you with an accurate assessment of a problem if you've solved it yourself. Any time-estimate they provide to fix it can also be better calculated if you've had to do it yourself. Every web site relies on a variety of factors, usually unseen, in order to continue to function properly. But the fact is that they misbehave from time to time. Deciding whether to tackle those problems yourself depends on your available time and skill set, and what it will require to get things back on track. In other words, it's a standard cost-benefit analysis that everyone has to undertake every day in life.