August 2002 - WLUG - wlug.mailman3.com

USB Support in Linux 2.4.18

by chuck

How can I tell if a specific USB device, in this case a removable USB hard drive, is supported by my kernel? I know that Linux 2.4.18 has "support" for USB devices. Does this mean all USB devices or just a few? I would think that the OS talks to the USB controller via a series of well documented commands and that its up to the controller to talk to the specific USB device. Does this make sense, or is there more to it? Thanks, Chuck

Aug. 11, 2002

Re: [Wlug] dhcp clients

by Brad Noyes

On Sat, Aug 10, 2002 at 01:04:49PM -0400, Charles R. Anderson wrote: > On Sat, Aug 10, 2002 at 11:47:52AM -0400, Brad Noyes wrote: > maitre> Hi All, > maitre> I got my home network rigged up to do dynamic dns with dhcp. It seems that the > maitre> linux and fBSD dhcp clients don't send the hostname to the dhcp server, so no > maitre> name record is created for those clients. Does anyone know how to do this? > maitre> (windows clients seem to send the hostname okay). wow ... first i'll answer your questions. > > What is the DHCP server? What is the DNS server? How are the servers > configured? DHCP server from ISC dhcpd-3.0p11 DNS server from ISC bind-9.1.3 (both on same machine, OS is OpenBSd) they are configured so the dhcpd gets a request and updates named, both A records and PTR records > > If you are using ISC dhclient, you can configure /etc/dhclient.conf with > a line like this: > > send host-name "foo.bar"; > > or if you want your configured hostname to override what the server > sends back: > > supercede host-name "foo.bar"; ahhh, okay i get it. I did a seach for dhclient.conf on my client machien and i couldn't find one, so i created one, read the man page, and i was able to get linux to send the hostname. > > However, there may be more to the story than just that... > > There are a few different ways DDNS can be done. One way is to have the > DHCP client update the forward DNS itself, and tell the DHCP server to > update the reverse DNS to match. That way the client can choose it's > own DNS name, and tell the DHCP server to set the PTR record to that > name (since the DHCP server will have the authority to update PTR > records in the subnets it is serving). Of course, the client must have > permissions on the forward DNS zone to update it. Usually TSIG or SIG0 > cryptographic signatures are used to provide secure DNS updates for this > purpose (however Windows DNS servers don't support TSIG or SIG0, only > the GSS proprietary protocol). This is something that i don't want becuase i have a windows clients in the house. > > The other way is to have the DHCP server update BOTH the forward and > reverse DNS. In this case, usually the server dictates both the forward > and reverse DNS domains, and can either use the client-provided hostname > or choose it's own hostname for the client. This is what i have at the moment. The networks is small enough where i know that names will not colide. > > These behaviors are controlled by the DHCP FQDN option (82). The client > can request that it update the forward DNS, or request that the server > update the forward DNS. The server can either accept what the client > requests, or reject it. If the server rejects the client's requests for > the client to update the DNS, the client should not attempt to perform > the update. i have the dhcpd server do all the work. Easier for me to control and i don't have to create keys for all the clients. > ISC DHCP supports the standard form of DDNS described above (unsecure > updates or TSIG security only). You can't update Windows DNS servers > securely with it. You can however update Windows DNS servers if > security isn't configured, or you can have a Windows DHCP server update > so-called "legacy" clients without using the DDNS protocol above. > Having never used Windows DHCP/DNS servers, I wouldn't know how to > configure that... All the servers involved are on OpenBSD so this is not a problem. > > To have the ISC dhclient perform DDNS and update it's own A record put > this in dhclient.conf: > > send fqdn.fqdn "foo.bar."; > send fqdn.encoded on; > send fqdn.server-update off; > > Change the last option to "on" to request the server to update the A > record. The server is doing the updating here so i would have this set to 'on' > > There may be more stuff to configure, such as zone statements and keys, > depending on what servers you are using and how they are configured... This is plenty on information for the time being. I think i have most things working now. Thanks Charles! --brad

Aug. 10, 2002

Re: [Wlug] dhcp clients

by Charles R. Anderson

On Sat, Aug 10, 2002 at 11:47:52AM -0400, Brad Noyes wrote: maitre> Hi All, maitre> I got my home network rigged up to do dynamic dns with dhcp. It seems that the maitre> linux and fBSD dhcp clients don't send the hostname to the dhcp server, so no maitre> name record is created for those clients. Does anyone know how to do this? maitre> (windows clients seem to send the hostname okay). What is the DHCP server? What is the DNS server? How are the servers configured? If you are using ISC dhclient, you can configure /etc/dhclient.conf with a line like this: send host-name "foo.bar"; or if you want your configured hostname to override what the server sends back: supercede host-name "foo.bar"; However, there may be more to the story than just that... There are a few different ways DDNS can be done. One way is to have the DHCP client update the forward DNS itself, and tell the DHCP server to update the reverse DNS to match. That way the client can choose it's own DNS name, and tell the DHCP server to set the PTR record to that name (since the DHCP server will have the authority to update PTR records in the subnets it is serving). Of course, the client must have permissions on the forward DNS zone to update it. Usually TSIG or SIG0 cryptographic signatures are used to provide secure DNS updates for this purpose (however Windows DNS servers don't support TSIG or SIG0, only the GSS proprietary protocol). The other way is to have the DHCP server update BOTH the forward and reverse DNS. In this case, usually the server dictates both the forward and reverse DNS domains, and can either use the client-provided hostname or choose it's own hostname for the client. These behaviors are controlled by the DHCP FQDN option (82). The client can request that it update the forward DNS, or request that the server update the forward DNS. The server can either accept what the client requests, or reject it. If the server rejects the client's requests for the client to update the DNS, the client should not attempt to perform the update. ISC DHCP supports the standard form of DDNS described above (unsecure updates or TSIG security only). You can't update Windows DNS servers securely with it. You can however update Windows DNS servers if security isn't configured, or you can have a Windows DHCP server update so-called "legacy" clients without using the DDNS protocol above. Having never used Windows DHCP/DNS servers, I wouldn't know how to configure that... To have the ISC dhclient perform DDNS and update it's own A record put this in dhclient.conf: send fqdn.fqdn "foo.bar."; send fqdn.encoded on; send fqdn.server-update off; Change the last option to "on" to request the server to update the A record. There may be more stuff to configure, such as zone statements and keys, depending on what servers you are using and how they are configured... -- Charles R. Anderson <cra(a)wpi.edu> / http://angus.ind.wpi.edu/~cra/ PGP Key ID: 49BB5886 Fingerprint: EBA3 A106 7C93 FA07 8E15 3AC2 C367 A0F9 49BB 5886

Aug. 10, 2002

dhcp clients

by Brad Noyes

Hi All, I got my home network rigged up to do dynamic dns with dhcp. It seems that the linux and fBSD dhcp clients don't send the hostname to the dhcp server, so no name record is created for those clients. Does anyone know how to do this? (windows clients seem to send the hostname okay). Thanks, --brad

Aug. 10, 2002

Re: [Wlug] Wireless antennas

by Wesley Allen

Hey, how much are these things. I have access in my whole house, but when I go in my backyard it's really hit or miss. Wes On Fri, 2002-08-09 at 08:10, Frank Sweetser wrote: > On Thu, Aug 08, 2002 at 11:04:14PM -0400, Andy Stewart wrote: > > > > HI gang, > > > > I have discovered that there are a couple of locations in my house where the > > wireless network does not work well at all. Naturally, they are the > > locations where I most want to use my laptop. > > > > My access point is on the 2nd floor in approx. the middle of that floor. I'm > > trying to use the laptop on the 1st floor at one end of the house to (almost) > > no avail. Moving the access point to other locations in the room seems to > > make little difference. My house is not a mansion - I'm well within the 300 > > ft alleged range. My 2.4 GHz wireless phones have no problem over this > > particular path through the house (and yes, I turned them off in case they > > were causing interference). > > > > I have been looking at these add-on antennas that are available on the > > Internet. It appears that some are passive while others are active. Would > > this help, or is there some more basic solution which I've overlooked? > > The catch with these add-on antannas is that they get you more effective power > by limiting the direction in which they're broadcast. If you can find one > corner of the house, you should be able to get away with an antenna that has > just a 180 cone, instead of a full omnidirectional one, that will give you > twice the effective signal strength. Also, if you access point has dual > antennas, then you can leave one as the omnidirectional, and get a directional > for the other antenna and point it at the problem spots. > > -- > Frank Sweetser fs at wpi.edu, fs at suave.net | $ x 18 > Full-time WPI Network Engineer, Part time Linux/Perl guy | > Right now I'm having amnesia and deja-vu at the same time. I think > I've forgotten this before. -- Stephen Wright > > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- This message may be digitally signed. For my public key, e-mail me a request.

Aug. 9, 2002

Re: [Wlug] Wireless antennas

by RB

Andy, Passive antennas work best when there the signal is low. It usually won't do a whole heck of a lot if the signal isn't there to begin with. I've done a couple of installations where I've used multiple antennas located in different parts of the building. The Linksys systems use two antennas for diversity reception. I've taken one of them and attached it to coax and an antenna and placed it in the "problem" room. It will reduce the overall range somewhat (since you'll lose your diversity reception capabilities) but it will fill the area you want the signal in. If you want to you can also put another antenna in a second "problem" room. This would of course change the center of your coverage area but if the antennas used have high enough gain to overcome the coax loss then you may actually gain some range in certain directions. The whole key is to put the signal where you want it. You'll sometimes trade off your signal in one location to improve it in another. This isn't always a bad thing. - Rob On Thursday 08 August 2002 11:04 pm, Andy Stewart wrote: > HI gang, > > I have discovered that there are a couple of locations in my house where > the wireless network does not work well at all. Naturally, they are the > locations where I most want to use my laptop. > > My access point is on the 2nd floor in approx. the middle of that floor. > I'm trying to use the laptop on the 1st floor at one end of the house to > (almost) no avail. Moving the access point to other locations in the room > seems to make little difference. My house is not a mansion - I'm well > within the 300 ft alleged range. My 2.4 GHz wireless phones have no > problem over this particular path through the house (and yes, I turned them > off in case they were causing interference). > > I have been looking at these add-on antennas that are available on the > Internet. It appears that some are passive while others are active. Would > this help, or is there some more basic solution which I've overlooked? > > Thanks, > > Andy -- -= rb(a)millbury.net =-

Aug. 9, 2002

Re: [Wlug] Wireless antennas

by Frank Sweetser

On Thu, Aug 08, 2002 at 11:04:14PM -0400, Andy Stewart wrote: > > HI gang, > > I have discovered that there are a couple of locations in my house where the > wireless network does not work well at all. Naturally, they are the > locations where I most want to use my laptop. > > My access point is on the 2nd floor in approx. the middle of that floor. I'm > trying to use the laptop on the 1st floor at one end of the house to (almost) > no avail. Moving the access point to other locations in the room seems to > make little difference. My house is not a mansion - I'm well within the 300 > ft alleged range. My 2.4 GHz wireless phones have no problem over this > particular path through the house (and yes, I turned them off in case they > were causing interference). > > I have been looking at these add-on antennas that are available on the > Internet. It appears that some are passive while others are active. Would > this help, or is there some more basic solution which I've overlooked? The catch with these add-on antannas is that they get you more effective power by limiting the direction in which they're broadcast. If you can find one corner of the house, you should be able to get away with an antenna that has just a 180 cone, instead of a full omnidirectional one, that will give you twice the effective signal strength. Also, if you access point has dual antennas, then you can leave one as the omnidirectional, and get a directional for the other antenna and point it at the problem spots. -- Frank Sweetser fs at wpi.edu, fs at suave.net | $ x 18 Full-time WPI Network Engineer, Part time Linux/Perl guy | Right now I'm having amnesia and deja-vu at the same time. I think I've forgotten this before. -- Stephen Wright

Aug. 9, 2002

Re: [Wlug] Issues with aic7770?

by Skip Gaede

On Thursday 08 August 2002 14:55, Keller, Tim wrote: > Has anybody done a Red Hat 7.3 install on a box with an > Adaptec 7770 card in it? The machine was running *cough* > the server version 4.0 of an OS that rhymes with "Empty" > and working fine. > > However, when boot off the CD due to our buddy "El > Torito" and INT13. The bios is able to get the diskette > image but then unable to find the CD. I've got a ftp > site with RH 7.3 so I point to it and everything works > fine until I have to specify which driver I'd like to use > for the scsi card. When I specify the Adaptec 7xxx > series driver, the kernel issues an "Opps" and continues > on. > Hi Tim, I have an Adaptec 2940UW card, and HeadRat insists on trying to use the highest possible speed to talk to my older drives. Mandrake, on the other hand, works well. I think your choices are to use and IDE drive with RH or use a different distro. --Skip

Aug. 9, 2002

Re: [Wlug] Wireless antennas

by Brian J.Conway

> I have been looking at these add-on antennas that are available on the > Internet. It appears that some are passive while others are active. > Would this help, or is there some more basic solution which I've > overlooked? Well, I know of some people that have put two WAPs in their houses, at around the middle height in each half of the house. That would require shelling out another $150, of course, but they do get full reception anywhere in the house. Brian J. Conway bconway(a)alum.wpi.edu "Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves." - Albert Einstein

Aug. 9, 2002

Wireless antennas

by Andy Stewart

HI gang, I have discovered that there are a couple of locations in my house where the wireless network does not work well at all. Naturally, they are the locations where I most want to use my laptop. My access point is on the 2nd floor in approx. the middle of that floor. I'm trying to use the laptop on the 1st floor at one end of the house to (almost) no avail. Moving the access point to other locations in the room seems to make little difference. My house is not a mansion - I'm well within the 300 ft alleged range. My 2.4 GHz wireless phones have no problem over this particular path through the house (and yes, I turned them off in case they were causing interference). I have been looking at these add-on antennas that are available on the Internet. It appears that some are passive while others are active. Would this help, or is there some more basic solution which I've overlooked? Thanks, Andy -- Andy Stewart, Founder Worcester Linux Users' Group Worcester, MA USA http://www.wlug.org

Aug. 9, 2002