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There are times when you'll want or need to upgrade your equipment. As your site grows, it will require better hardware to perform routine tasks. Standards change over time, and hardware you couldn't afford when you started suddenly comes into your price range. Or you simply decide to offer more services that require hardware you don't have yet.
The primary issues sites have to contend with when it comes to hardware are bandwidth and hard drive space. Sites eventually require greater bandwidth as the number of users increases, and the options on the Internet include more and more bandwidth-intensive services, such as the World Wide Web and various voice and voice/video transmission protocols. Hard drive space easily gets eaten up in time, as you and your users take up all of the space you can, and your services get larger, and you get more users on your site.
In this chapter, you learn:
Hardware upgrading refers to anything from adding RAM to adding printers or even purchasing a whole new server. There are a number of important factors to keep in mind when choosing brands and models of equipment for your site. For advice on how much memory, hard drive space, etc., that your site will require, read Chapter 2, "What Kind of Hardware and Connection You'll Need."
The following is a quick review of which aspects of a computer's hardware effect which aspects of performance:
When purchasing equipment for a Linux system, don't choose a brand entirely by the features that are listed on the packaging. The programs that come with most hardware (e.g., tape backup systems) are written for MS-DOS or MS-Windows systems, so you can't always count on using some of their special features.
Be sure that you look at the "Linux Hardware How-To" in appendix F before purchasing any hardware for your system. There is nothing worse than getting a component and then discovering you can't find any drivers for it!
As new versions of the kernel come out, more and more hardware is supported. Check the most recent version of the Hardware How-To in the Linux Documentation Project files if you want to see if something in particular has been added. Then, just get the necessary patches from Sunsite to upgrade your kernel to that level.
You may find that if you're willing to go to an experimental kernel, you can find drivers available for a particular piece of hardware that weren't available before. See chapter 16, "Upgrading Your Software," for more on experimental kernels and the pros and cons.
You probably remember being impatient as a user with every second of downtime your own provider had. Your users will be the same with you. I'll go over some methods here of making sure that you minimize your downtime as much as possible. By keeping your downtime minimal, you not only make your users happy, but your life gets easier because you don't have as many complaints coming in.
Be sure the hardware you purchase is compatible with your system. Check out new versions of the Linux Hardware How-To (available at Sunsite and on the Linux Documentation Project Web pages) and be sure to get something on that list. Look at the drivers required to support this hardware, and see which kernel these drivers were introduced in. Be fully aware of the work you'll have to do to install one brand which may only work with a brand new, experimental driver, over another which may have a driver in your current kernel that's perfectly stable.
Give your users as much warning as possible, including an estimation of how long the system will be down. You may be tempted to give a nice short guess, but keep in mind that you may run into unforeseen problems. Keep in mind also that most experienced users will add a few hours to whatever estimates you give them, so don't overestimate either.
Remember, if it's going to take 8 hours or more to get something repaired, you're going to have to arrange to feed the people doing the work!
If you run a large site, you may want to pay someone to stay until later at night (e.g., 10 pm), or even keep technical staff in 24 hours a day, seven days a week. People who use the Internet for work and fun tend to do it at all sorts of hours, and appreciate being able to get at least bigger problems solved when they come up (e.g., one of your site's computers going down.
Have a distinct plan ready when you take the system down. Know all of the steps you will need to take, and try to know some of the more common problems. The more informed you are, the more quickly the operation will be finished.
This means reading all of the instructions for all of the software and hardware you're dealing with beforehand. If there are FAQs available on the net, read those too.
Another part of being prepared is making sure all of your cables will connect up properly to one another! There's little worse than having all of the equipment on hand but finding out you're trying to connect a female cable to a female port and don't have a converter on hand.
If you're dealing in any way with your file systems, make backups! If you're even just concerned that something might happen to your file systems during the upgrade, make backups. When it comes to backups, it's better to have spent the time making them and not need them than to need them and not have them.
Also, it's highly useful to make a backup of your file listings with the permissions in tact. On occasion most system administrators slip up and type the wrong thing in the wrong place, and half of your file permissions are suddenly completely wrong. If you've kept a backup of how things should be set, you can refer back to it rather than just having to see what won't work to track the problems down!
If you're simply pulling one computer out from your Ethernet network, don't forget that you need to keep the cabling plugged into the card if you're keeping the rest of the site up and running. If an Ethernet connector is so much as jiggled out of place on one machine, all of your machines will lose their networking.
Another way to handle it if you're working on the machine at the end of your network, is to move your ethernet terminator up by one machine. This way, you have a new end of network defined for a while, so everything stays up and running.
Basically, there has to be a terminator at both ends of your network. If one of your connections comes loose, you suddenly have an end of network without a terminator, because the network can't pass the point where the connection isn't there. Moving your terminator and cutting off part of the network if you're going to work on a machine in the middle may be the only way to work on it without shutting the whole network down.
Try to have a backup plan in case the new setup doesn't function properly. For example, don't write off the old hardware immediately (unless the whole reason for the change is that something was broken). Keep things around for a week or so in case something malfunctions.
Plus, you may want the old items one day to install on a new machine for a transitional period before you go out to buy nicer equipment. I've even run into occasions when an old dial-in modem needed to be put into a slot where a new modem had been because the user assigned to that line had a modem that wasn't compatible with the newer one. So, as long as you have the room to store it, you may as well keep the majority of the old hardware that was only removed because it was obsolete, around.
When it comes to memory chips, you may want to actually call your computer's motherboard manufacturer. Some SIMMs just don't work with some motherboards, even though they should according to their specs. (There should be a listing in the manual of what kind of SIMMs your motherboard requires.) Of course, it's easy enough to remove the offending SIMM and get it replaced if it doesn't work. It just means that you suddenly don't have that extra RAM you thought you'd have at that point.
See chapter 2, "What Kind of Hardware and Connection you'll Need," for more on specific hardware considerations and types.
Connection upgrades require a lot of forethought. This is especially important when major hardware changes are required, such as new kinds of modems or having new lines put in. After all, technology changes rapidly, and you don't want to find that your expensive connection upgrade wasn't the way to go!
It's a good idea to keep in touch with both your phone company and your provider concerning connection options. Keep up-to-date on their plans involving their own technology upgrades, short and long term. You may find that you can afford a sensible upgrade earlier than you thought, or that it's not the right time to move to the next level because something better is coming around the corner.
For more on the various types of connections available, see Chapter 2, "What Kind of Hardware and Connection You'll Need."
Let's do a quick review of the connection types that are available and some of the considerations you need to make, in order of connection speed.
Upgrading from a single 28.8 to a paired 28.8 modem setup requires a few things. First, check with your provider to see if they support load balancing. Then, find out how much they charge. It may be that they charge you for two full Internet connections. If they do this, find out how much an ISDN connection costs, it may be close to the total cost of the load balancing.
If the connection is cost feasible, then you'll first need to make sure that your server has enough serial ports to handle the extra modem. If not, you may need to get a new multiport serial card to handle it. Also, of course, you'll need to get the second modem. I personally prefer external modems because you can monitor the data lights and know your connection's status at a glance. You will also need an extra standard phone line to carry the second modem's data.
See chapter 2, "What Kind of Hardware and Connection You'll Need" for how to set up your load balancing connection.
If you are moving from a 28.8 based connection to an ISDN connection, you once again first need to make sure your provider can offer you an ISDN connection on their end. You also need to make sure the local phone company can offer you an ISDN connection to your home.
If this is possible, then you can cancel the phone line that you use for your modem connection to the Internet unless you have another use for it. You can also remove the 28.8 modem handling it from your machine.
You can always use that extra line and modem for an incoming dial-in connection.
From this point, you'll need to obtain the equipment discussed in chapter 2. You may find it helpful to talk to your service provider and phone company about what kind of equipment is best to work well with theirs.
As usual, you need to first contact your service provider to see if they can offer you an FT1 or a T1 connection. You may find that they can't, as they may not have the bandwidth to feed that fast of a connection through. If you do find you have to switch providers, remember that you have to go through InterNIC and make sure and file a routing change. Your old provider or the new one will likely be willing to handle this for you since they'll want the transition to go smoothly.
You also need to check with your phone company. They will have to lay a T1 line to your site, and this can get costly if the area you're in doesn't have a digital line structure already. If it's going to be a costly installation, put some serious thought into how long you plan to be at that site. If you have plans to move soon, you may want to go ahead and do so.
As with upgrading to ISDN, your 28.8 modem (if that's what you're upgrading from) and the standard phone line you used it with is no longer necessary for connecting your site to the Internet.
From here, see chapter 2 for more on selecting your equipment. Your provider, phone company, and even local computer consultants would be good people to talk to about equipment. You can also research brands and options on the Internet via the World Wide Web, and get information at computer shows.
The considerations for a T3 are mostly the same as for a T1. Keep in mind that you can use multiple T1 connections before you need to upgrade to a whole new connection type. The phone company will once again have to wire a new line to your site, as T3 doesn't use the same exact wiring as a T1 (that's how it gets more bandwidth). This also means you will have to get a new interface between the line and your system, because it will be a different size wire you're plugging in. See chapter 2, and talk to your phone company, provider, and local computer consultants for more on choosing equipment for this type of connection.
You may want to contact your local cable company and find out how soon it will be before they're offering Internet connectivity through their coaxial cables. You will have the many of the same considerations as before when it comes to equipment, except that you'll likely have to get the specialized equipment straight from the cable company. More on this in chapter 2.
