DHCP reverse DNS in Linksys LAN environment
Long story short: a friend began the setup of a debian box for me (i'm a little overbusy with work and a very long commute), wasn't familiar with debian, never seemed to get it, eventually gave up in frustration. So, i'm now trying to decipher the setup of a box with stable r 6 installed. I've the details of the current LAN setup below. From any one of the laptops we can telnet to the Debian box's IP address. The connection happens almost immediately (an event logged in syslog and, depending on the telnet client, the message that connection has been made appears). Then there is a very long wait before the login message appears. I'm pretty sure this is a DNS lookup issue. What I'd like to do is configure the Debian box so that if it sees an IP in the DHCP range of the LAN it doesn't do reverse lookup. On the other hand, if I should be using the Lynksys box as a nameserver in /etc/resolv.conf let me know! My next step will be getting the box to see the outside world. I've never set up a system using a Linksys box or in a DHCP environment. While my friend's home network is also behind a Lynksys box, they have a number of assigned static IPs -- they don't have the DHCP range issue. Thanks for any thoughts and pointers. Cheers, judith NETWORK CONDITION: We have a home LAN behind a Linksys DSL router (model BEFSER41). The Debian box has a static routing path set up in the Linksys system. The other systems (Win ME laptop, OS X 10.1 laptop, and Win98 box) have dynamic address. The other systems all have names available and visible on the SMB/Microsoft Network nonsense. There are no domain names in use locally by the laptops and Win98 box. The Debian box thinks its domain is grey-cat.net (and I plan to eventually use something like zoneclient from zoneclient.sourceforge.net to use that domain for the box). telnetd is running on the Debian box. The Debian box can ping a laptop on the LAN successfully (by IP address); it cannot ping the outside world. A laptop can ping the Debian box successfully (by IP address), as well as anywhere else in the outside world . My friend says he had the Debian box so it could connect to the 'net from his home LAN. I've commented out all his nameservers from resove.conf and confirmed I my ISP's nameserver specified. If I should be using the Lynksys box as a nameserver in /etc/resolv.conf let me know! -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
On Sun, 2 Jun 2002 11:12:59 -0500 Judith Elaine Bush [EMAIL PROTECTED] wrote: We have a home LAN behind a Linksys DSL router (model BEFSER41). (snip) The Debian box can ping a laptop on the LAN successfully (by IP address); it cannot ping the outside world. A laptop can ping the Debian box successfully (by IP address), as well as anywhere else in the outside world . (snip) I've commented out all his nameservers from resove.conf and confirmed I my ISP's nameserver specified. So, you're using the Linksys DSL router to provide NAT'd access out to the Internet, correct? All DHCP assigned systems can ping internal and external hosts, correct? Sounds like the statically assigned Debian system doesn't have a default gateway assigned. What does /sbin/route -n return on the Debian system? -- Jamin W. Collins -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
On Sun, Jun 02, 2002 at 11:28:51AM -0500, Jamin W. Collins wrote: On Sun, 2 Jun 2002 11:12:59 -0500 Judith Elaine Bush [EMAIL PROTECTED] wrote: We have a home LAN behind a Linksys DSL router (model BEFSER41). (snip) The Debian box can ping a laptop on the LAN successfully (by IP address); it cannot ping the outside world. A laptop can ping the Debian box successfully (by IP address), as well as anywhere else in the outside world . (snip) I've commented out all his nameservers from resove.conf and confirmed I my ISP's nameserver specified. So, you're using the Linksys DSL router to provide NAT'd access out to the Internet, correct? All DHCP assigned systems can ping internal and external hosts, correct? Yes yes. Sounds like the statically assigned Debian system doesn't have a default gateway assigned. What does /sbin/route -n return on the Debian system? The answer is below. Should the Gateway be the IP address of the Linksys box? I'll be trying that before I leave in 15 minutes. Thanks very much for the quick pointer. judith Kernel IP routing table Destination Gateway Genmask Flags Metric RefUse Iface 192.168.1.0 0.0.0.0 255.255.255.0 U 0 00 eth0 0.0.0.0 192.168.1.250 0.0.0.0 UG0 00 eth0 When I looked at this a few weeks ago I noticed the loopback wasn't there. I added it by hand so the output of route -n was as follows, but had the same problems (not surprisingly). Kernel IP routing table Destination Gateway Genmask Flags Metric RefUse Iface 127.0.0.1 0.0.0.0 255.255.255.255 UH0 00 lo 192.168.1.0 0.0.0.0 255.255.255.0 U 0 00 eth0 0.0.0.0 192.168.1.250 0.0.0.0 UG0 00 eth0 And FYI... $/sbin/ifconfig eth0 Link encap:Ethernet HWaddr 00:A0:CC:64:6B:97 inet addr:192.168.1.30 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6115 errors:0 dropped:0 overruns:0 frame:0 TX packets:3797 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 Interrupt:10 Base address:0x9000 loLink encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 UP LOOPBACK RUNNING MTU:3924 Metric:1 RX packets:49 errors:0 dropped:0 overruns:0 frame:0 TX packets:49 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
On Sun, 2 Jun 2002 12:03:08 -0500 Judith Elaine Bush [EMAIL PROTECTED] wrote: The answer is below. Should the Gateway be the IP address of the Linksys box? I'll be trying that before I leave in 15 minutes. Thanks very much for the quick pointer. Yes. Once the gateway entry is correct (the IP of the Linksys router) you should be good. At that point if pinging by name doesn't work. I would try a few pings by IP (ping a few hosts from one of the other boxes and use the returned IP on the Debian box), this will help determine if there's a problem with name resolution. -- Jamin W. Collins -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
On Sun, Jun 02, 2002 at 12:16:30PM -0500, Jamin W. Collins wrote: On Sun, 2 Jun 2002 12:03:08 -0500 Judith Elaine Bush [EMAIL PROTECTED] wrote: The answer is below. Should the Gateway be the IP address of the Linksys box? I'll be trying that before I leave in 15 minutes. Thanks very much for the quick pointer. Yes. Once the gateway entry is correct (the IP of the Linksys router) you should be good. At that point if pinging by name doesn't work. I would try a few pings by IP (ping a few hosts from one of the other boxes and use the returned IP on the Debian box), this will help determine if there's a problem with name resolution. I haven't tested whether the long delay with telnet has gone away, but the Debian box can now see the rest of the world. I suspect my friend's Linksys box has a different LAN IP than mine. Thanks! judith -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
On Sun, 2 Jun 2002 12:20:35 -0500 Judith Elaine Bush [EMAIL PROTECTED] wrote: I haven't tested whether the long delay with telnet has gone away, but the Debian box can now see the rest of the world. I suspect my friend's Linksys box has a different LAN IP than mine. The changes to the gateway address being used by the Debian system should have little impact on the delay you are seeing in your telnet sessions starting. As I don't use telnet on my systems (I much prefer SSH) I don't have any sure fire advice for you. However, you may want to look into in.telnetd (believe that's the daemon for telnet servers) and see if there isn't a command line switch that controls whether a DNS lookup is performed or not. Then check how it's being started from your /etc/inetd.conf -- Jamin W. Collins -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: DHCP reverse DNS in Linksys LAN environment
The changes to the gateway address being used by the Debian system should have little impact on the delay you are seeing in your telnet sessions starting. As I don't use telnet on my systems (I much prefer SSH) I don't have any sure fire advice for you. However, you may want to look into in.telnetd (believe that's the daemon for telnet servers) and see if there isn't a command line switch that controls whether a DNS lookup is performed or not. Then check how it's being started from your /etc/inetd.conf Probably the inetd is running with logging enabled. Which means that it will reverse lookup all IP addresses and try to log the name in /var/log/syslog. Check syslog and see if inetd is logging there. Bob -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Exim does unwanted DNS lookups for LAN
Hi, I've a problem with Exim; I couldn't figure out what's wrong with my configuration, so I'm asking here for help... My LAN consists of two hosts (both running Debian 2.2 with Exim): orion.sc (192.168.0.1), which is the Gateway and gryffindor.sc (192.168.0.2). orion should be the SMTP smarthost for gryffindor, it should forward mail To: *.sc (local mail) to these hosts and it should forward outgoing mail to another smarthost (on the internet). I don't have a local DNS server, the /etc/hosts on both hosts has these entries: 192.168.0.1 orion.scorion 192.168.0.2 gryffindor.sc gryffindor I can reach the hosts with their names without problem. My router section in /etc/exim.conf on gryffindor looks like this: ## # ROUTERS CONFIGURATION # [...] # Send all mail to a smarthost smarthost: driver = domainlist transport = remote_smtp route_list = * orion.sc byname end I *wrote* byname, which tells Exim to use gethostbyname() to find the IP address of orion and not bydns_* BUT, Exim *still* makes DNS lookups for orion.sc, which is very annoying, 'cause this establishs a connection to the internet. It fixes the problem if i set the route_list to * 192.168.0.1 byname - but I don't understand why * orion.sc byname doesn't work. Well, it works, if I remove the default gateway on gryffindor pointing to orion, but sure that's not the solution. The router section on orion looks like this: ## # ROUTERS CONFIGURATION # [...] # Deliver mail to the local net via gethostbyname(), not via DNS lan: driver = domainlist transport = remote_smtp route_list = *.sc $domain byname # Send all mail to a smarthost smarthost: driver = domainlist transport = remote_smtp route_list = * smtprelay.t-online.de bydns_a end Here's the same problem; Exim establishs a internet connection because of a DNS lookup. In both cases, the mail gets delivered correctly, but it should work without establishing a internet connection. Can somebody please tell me what am I missing? Thanks, moritz moritz -- Moritz Schulte [EMAIL PROTECTED] http://hp9001.fh-bielefeld.de/~moritz/ Debian/GNU supporter - http://www.debian.org/ http://www.gnu.org GPG fingerprint = 3A14 3923 15BE FD57 FC06 B501 0841 2D7B 6F98 4199
Re: Exim does unwanted DNS lookups for LAN
Hi Moritz! Here's the same problem; Exim establishs a internet connection because of a DNS lookup. In both cases, the mail gets delivered correctly, but it should work without establishing a internet connection. Can somebody please tell me what am I missing? Can they ping each other using names without doing DNS lookups? -- Sean Furey, a happy and satisfied Debian user. [EMAIL PROTECTED]
Re: Exim does unwanted DNS lookups for LAN
Sean Furey [EMAIL PROTECTED] writes: Hi Moritz! Hi, Can they ping each other using names without doing DNS lookups? Yes, without problems. moritz -- Moritz Schulte [EMAIL PROTECTED] http://hp9001.fh-bielefeld.de/~moritz/ Debian/GNU supporter - http://www.debian.org/ http://www.gnu.org GPG fingerprint = 3A14 3923 15BE FD57 FC06 B501 0841 2D7B 6F98 4199
Re: Exim does unwanted DNS lookups for LAN
try putting the local servers in /etc/hosts Jeff Sean Furey wrote: Hi Moritz! Here's the same problem; Exim establishs a internet connection because of a DNS lookup. In both cases, the mail gets delivered correctly, but it should work without establishing a internet connection. Can somebody please tell me what am I missing? Can they ping each other using names without doing DNS lookups? -- Sean Furey, a happy and satisfied Debian user. [EMAIL PROTECTED] -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of unsubscribe. Trouble? Contact [EMAIL PROTECTED]
Re: Exim does unwanted DNS lookups for LAN
Jeff Green [EMAIL PROTECTED] writes: try putting the local servers in /etc/hosts They are in /etc/hosts - on both hosts. moritz -- Moritz Schulte [EMAIL PROTECTED] http://hp9001.fh-bielefeld.de/~moritz/ Debian/GNU supporter - http://www.debian.org/ http://www.gnu.org GPG fingerprint = 3A14 3923 15BE FD57 FC06 B501 0841 2D7B 6F98 4199
dns in an LAN?
Hi I have an debian linux box as server in an local area network, where all clientes machines are in Windows. I have not an DNS server, thus all IP/name translations are doing through the /etc/host file that I have in every machine. I want install an DNS server in my linux box to avoid the modificy every /etc/host file in every machine when a newer client machine is add to the network,but.how can I do it? I just intalled the bind pakage,answer the cuestions it made me in the installation, but how can I say it the IP address and names of the network machines? thanks. bye -- TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word unsubscribe to [EMAIL PROTECTED] . Trouble? e-mail to [EMAIL PROTECTED] .
Re: dns in an LAN?
At 10:33 PM 7/24/97 +0200, you wrote: I just intalled the bind pakage,answer the cuestions it made me in the installation, but how can I say it the IP address and names of the network machines? Check out the DNS Howto at: http://sunsite.unc.edu/mdw/HOWTO/DNS-HOWTO.html I just setup my on domain and this Howto was perfect. Syd http://syd.onsyd.com/ How do you know you're having fun if there's no one watching you have it. Douglas Adams -BEGIN PGP PUBLIC KEY BLOCK- Version: 2.6.2 mQCNAzN3eq0AAAEEAMGqDqrPkUM0PEPT4UBXCVDylEkUabrkqq/yBk1koSqHWlxs 02wVIVl/2B33MuS1aF3XfjvQLH2J6VJTUtyOwH2yglfpyJ68/TaE7od2gT3V99ax a/bENj3x5xnCxQFuKJCBUi4l5CoHEEn8Og6I0IS3vz+nJFkKF0AiZe6TgKrhAAUR tCVTeWQgQWxzb2Jyb29rIDxhbHNvYnJzcEBlbWFpbC51Yy5lZHU+iQCVAwUQM3eI 00AiZe6TgKrhAQHMWAP/W/ZacyMwNrHF0LU3eMyzTbjeFotEws1FmmE2ALjTgVI2 emtsN7vynlZ17p4qPDPlO18G/PTQ2r61kIywmn3bApaTsij5wSXMYv+4VRUvs1wX Ie8gHs6jGZBa3wnutCzaDDW/VPy/atpvLSWTc7Mku1BJzee5whRxxw+QUK2KjD0= =EjnG -END PGP PUBLIC KEY BLOCK- -- TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word unsubscribe to [EMAIL PROTECTED] . Trouble? e-mail to [EMAIL PROTECTED] .
