27 new of 86 responses total.
I would appreciate some information about DHCP in IP/TCP. In the Network dialog in OS X I can implement automatic DHCP, but have no other control over it except to manually renew the DHCP lease. However in the Airport Base Station I'm using I can choose the DHCP lease term from minutes to days. What are the consequences of choosing a lease term? What happens at the time a lease "expires" (and does its expiration depend upon whether the computer, or Airport Base, is in use, idle, or off)? The default lease term on the Airport Base was 4 hours, and on some occasions I observed I no longer had internet access after my system had been idle for more than 4 hours. Is this related, or a coincidence, or what? If the former, how do I get a new lease immediately? Mac Help is pretty useless in regard to these questions.
The DHCP lease is something that the DHCP server sets, not the client. For your application I'd set the lease either off or for many days - a shorter lease is only useful if you have other clients connecting and needing a lease from a limited pool of IP addresses.
Makes sense. Now what might I experience at lease expiration if I set the term for several days (and how does this depend on whether the computers and/or the Airport router is always on and/or used intermittently)? Or maybe it is better to ask, what if any conditions of system operation and lease term setting will lead to any observable consequence of setting a finite lease term? It doesn't look like I can set the lease term to zero.
A lease term of 0 wouldn't make any sense. The lease term sets how long a client gets to hold onto an IP address before it has to ask to have it renewed. Setting the lease shorter means the IP will be available again sooner if the client goes away; setting it longer means that a client that isn't connected all the time will have a more stable IP address. It doesn't generally affect how often the client asks to have the lease renewed, though. My experience is that Windows machines, for example, will always ask for a renewal once every five minutes as long as they're online.
I'm trying to understand how this applies in my system, where I have two computers on a wired LAN that connects to a wireless router. I set the DHCP lease term on the *router*, which is on most of the time. The computers are shut down often. When the lease term was set to 4 hours, on occasion I could not connect from the computers until I had shut everything down and restarted. Can this behavior be explained with how the lease system works?
I don't think you should be losing connection that way.
I don't think that's related, unless there's a bug somewhere. All a lease term of 4 hours means is if the router doesn't hear from a particular computer for 4 hours, it releases that machine's IP address and may hand it out to another machine if a new request comes in. The original computer will still get an IP address when it asks for one again, it just may not be the one it had originally.
Here's what I get for the IP addresses of the various devices:
iMac G4 Bridge Router
10.0.1.2 10.0.1.3 192.168.30.1 10.0.1.1
69.137.222.90
I think that Bridge IP address is for accessing it's software to configure
it (?). The second one for the router is its "Public (WAN) IP address".
The router has a default setting of
"Share a single IP address (using DHCP and NAT)"
with an alternative, not being used of
"Share a range of IP addresses (using only DHCP)"
Does this tell anyone anything about how this system is working (and if
it might lead to a disconnection if the lease term in the router is 4
hours)?
It looks all right to me. It's a little odd that the bridge's address isn't in the same subnet, but for bridging purposes that really shouldn't matter.
How long does it take for the router to get a new IP address at the end of a lease term? If this can be a significant time, then I would have an increased probability of being able to connect anew while it is negotiating for a new lease if the lease term is short (like it was, at 4 hours). I have increased it to 4 days, and I have not encountered the inability to connect since.
Usually it doesn't take more than a second or two.
Is it possible for the ISP (Comcast, in this case) to run out of leases?
I get the impression that, with Comcast, *any*thing is possible. . . . But it should be improbable.
Given the 'always on' nature of cable internet, I would call it unethical to sell more accounts than they have IPs. So in correct operation it should not be possible for them to run out of leases. But as juicy says... I've had to debug and solve problems for them on a couple occasions.
I have a wired Ethernet LAN with two computers (iMac and G4) and a printer (Brother 2070N), connected with a wireless adapter to an Airport base station (and from that to a cable router). I can also connect to the internet through the base station from a Mac laptop. I would like to *print* with the printer on the LAN from the laptop. Is this possible and, if so, how? The Airport Extreme manuals only have information about printing to a USB printer connected to the base station.
Assuming the airport base station is like other wireless router/access points, the laptop should already be on the same network as the workstations and printer. Have you tried pinging the printer from the laptop?
From termimal? Using its DHCP IP address? I thought this was all built into OSX. The Printer Browser on the laptop shows the printer, but gives no location for it. (I'm in the dummy class for a lot of these networking details so I need help.)
I would think you should be able to access the printer like you would from the PCs. What kind of location information do the PCs give?
I got it to work with the DHCP IP address. The Mac Help helped but the procedure is not intuitive. What led me astray is that when I installed the printer software, it showed up in the printer selection menu, which I thought meant that it saw the printer. But no: one has still to Add the printer and give it an arbitrary name and location. There is then an obscure menu, which is hard to find, where one chooses the make and model of the printer (there are hundreds listed!).
Well, as unintuitive as it might have seemed, I can assure you it would have been much more confusing in Windows. :)
Case in point: My networked laser printer is in the basement while my windows PC is on the 2nd floor. If I add the printer to the windows PC, the "add printer wizard" asks if it is a local or network printer. You have to answer "local" in order to install it.
Another problem I had while trying to get to print across the network was that my wife was watching streaming video on the wired LAN while I was trying to print wirelessly from the laptop, which so jammed he pipe that none of my packets got to the printer until she shut down. I'm now wondering if I even had to install the printer driver on the laotop, since one of the steps in adding the printer was selecting a make and model from a dialog. Does OS 10.4 already have printer drivers?
Often there is a list of printers for you to install. And often the printer you have is not in that list until you install the software that came with it. Just to add some complexity here, if you can figure out how to force the base station to assign the same IP every time, or how to assign to the printer a static IP on the same network segment but outside the DHCP range, you may save yourself some trouble later on if the base station should ever decide to assign a different IP to the printer. Or you could just remember that this is a possibility and if the printer every mysteriously stops working start by checking what IP it is using.
I'll keep that in mind. So far, the IP assignments have been stable. I don't know where they come from, though.
The success I had in printing mentioned above was a one line test phrase. Now I am been trying to print a two page WORD document. I had two types of failures on repeated attempts: 1. After an hour or so *trying* to print, I got "Print file was was not accepted (client-error-not-found)! or 2. Error dialog "printer busy, will retry in 10 sec". This every now and then printed either a blank page or a page with just the first line of the document. What's gumming it up? Could it be the driver I installed when I really did not have to?
Re resp:80: Yeah, the Windows idea of "local printers" and "network printers'"is utterly confusing until you realize it's really asking whether it's a local *queue* or not. I suspect what Microsoft expects is that you'll tie all your network printers to one central Windows server, and then let all your desktop systems print through that machine, making the difference moot for typical users.
I wrote Brother (the printer maker) about the problem and they sent me the standard procedure for installing a printer uner OS X 10.4 on a network - but not on a composite wired and wireless network like I have. Anyway, I tried what they suggested, and it didn't work. Now I'm inquiring on an apple.com forum. It's a problem, though, in getting answers when the system involves a Mac computer and an Apple Airport router, a Brother printer, and a MacWireless adapter. Probably as bad as a Windows system.... Yes, the usual assumption in printing with an Airport WiFi system is that the printer is plugged in a USB or Ethernet port on the router. The Airport manual doesn't address the option of a LAN connected to the router wirelessly.
You have several choices: