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Only in the last week have I been having these difficulties. It started this past weekend, where the webserver I run off my FC3 box suddenly and inexplicably went down. I also could not connect via SSH, so all weekend (as I was at home, and my server is in my dorm room at college...this week starts spring break ) I had to sit at home and contemplate why on earth my server went down.
Monday at work, my webserver miraculously went back up! I could connect via SSH, view the web sites, and everything! All in perfect working order. However, around noon, once again it went down. I had a chance to visit my dorm room after work, and discovered that everything was, in fact, still running, but that somehow my server box had changed its network IP address. I have my desktop (WinXP) and server box (FC3) connected to a Linksys router. The desktop is 192.168.1.100, and the server box is .101. It has been that way for months now with no problems. However, when I discovered the IP change, my server (for whatever reason) had the IP of 192.168.1.102, which (logically) had broken the router's port forwarding.
The timing, though, was ironic: I've been busy all weekend configuring my hosts.allow and hosts.deny files, as SSH has been getting a loooot of hammerings, and I wanted to restrict its access to *only* my college's domain.
At the moment, I'm at work...quite busy, of course... so I can't SSH into my server and post the syslog files. However, as soon as I have a moment to sit down at the server I will post what is logged, and hopefully with those and everyone's vast linux knowledge I can figure out what's going on. Thanks!
In all honesty I don't think this is going to be a problem with your server at all. How do you have your Linksys router assigning IPs? Are you using DHCP or statically assigning the IPs? I had a similar issue a while ago with my Linksys router cycling the IP address on my network printer until I statically assigned the IP and made sure to only allow for exact number of IPs assigned via DHCP for my machines connected to my network. Since that time I have not had a problem with my printer miraculously getting a new IP address and me having to reconfigure software to print to it.
I had the router's DHCP server on, but in all reality that has only caused me headaches ever since I began running servers. Whenever I would need to reboot my comp (updates, clear out the RAM, etc), I would always get an IP address I didn't have before, and so everything would need to be reconfigured. What I don't understand, though, is why all of a sudden the IP address started changing without any action on my part (e.g. a reboot).
I reconfigured my linux box to assign its own IP statically, but for now I've left the router's DHCP server on, as I haven't had a chance to check whether or not my Winblows desktop statically assigns itself or queries the router. Also, I daisy-chain a wireless router to my Linksys router, and I've read that the wired router must have its DHCP server enabled for the daisy-chaining to work.
Hopefully I'll get those system logs posted this afternoon...thanks so much for the help!
Distribution: SuSE Linux Open/Enterprise, Red Hat, Ubuntu
Posts: 147
Rep:
Put the server into a DMZ zone. (assumming your router has that capability) The router will never attempt to assign an address to anything into a DMZ. You can keep the DHCP service on at the same time.
About the daisy-chaining, you dont need to have the DHCP service running for it to work. Daisy-chaining is merely an expansion of your existing network. So when a request is made on the wireless router, it will automatically send it to the wired router. (the wireless router and wired router act as one device, when you hook them up together)
Arg, I set my linux box to statically assign an IP address to itself, and a mere few hours it had a new IP address again! FInally I've had a chance to sit down at the server itself and copy the system logs - here they are:
Code:
Mar 23 12:21:54 irish dhclient: receive_packet failed on eth0: Network is down
Mar 23 12:21:54 irish dhclient: receive_packet failed on eth0: Network is down
Mar 23 12:21:54 irish kernel: eth0: link up, 100Mbps, full-duplex, lpa 0x45E1
Mar 23 12:21:55 irish dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3
Mar 23 12:21:55 irish dhclient: receive_packet failed on eth0: Network is down
Mar 23 12:21:56 irish dhclient: DHCPOFFER from 192.168.1.1
Mar 23 12:21:56 irish dhclient: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Mar 23 12:21:56 irish dhclient: DHCPACK from 192.168.1.1
Mar 23 12:21:56 irish NET: /sbin/dhclient-script : updated /etc/resolv.conf
Mar 23 12:21:56 irish dhclient: bound to 192.168.1.102 -- renewal in 37175 seconds.
Mar 23 12:26:33 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:27:10 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:28:12 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:28:45 irish ntpd[4928]: sendto(64.109.43.141): Invalid argument
Mar 23 12:29:24 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:30:02 irish ntpd[4928]: sendto(80.242.32.5): Invalid argument
Mar 23 12:30:36 irish ntpd[4928]: sendto(212.159.114.45): Invalid argument
Mar 23 12:30:59 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:31:36 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:32:46 irish last message repeated 3 times
Mar 23 12:33:50 irish last message repeated 2 times
Mar 23 12:35:14 irish last message repeated 2 times
Mar 23 12:37:19 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:40:34 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:40:55 irish sshd(pam_unix)[8817]: session closed for user magsol
Mar 23 12:45:20 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:45:50 irish ntpd[4928]: sendto(64.109.43.141): Invalid argument
Mar 23 12:46:01 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:46:37 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:47:06 irish ntpd[4928]: sendto(80.242.32.5): Invalid argument
Mar 23 12:47:42 irish ntpd[4928]: sendto(212.159.114.45): Invalid argument
Mar 23 12:49:29 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:50:59 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:53:19 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 12:54:43 irish last message repeated 2 times
Mar 23 12:56:38 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:00:09 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:01:01 irish crond(pam_unix)[8982]: session opened for user root by (uid=0)
Mar 23 13:01:01 irish crond(pam_unix)[8982]: session closed for user root
Mar 23 13:02:54 irish ntpd[4928]: sendto(64.109.43.141): Invalid argument
Mar 23 13:03:28 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:04:10 irish ntpd[4928]: sendto(80.242.32.5): Invalid argument
Mar 23 13:04:13 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:04:47 irish ntpd[4928]: sendto(212.159.114.45): Invalid argument
Mar 23 13:05:12 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:06:08 irish last message repeated 3 times
Mar 23 13:07:16 irish last message repeated 3 times
Mar 23 13:09:31 irish last message repeated 3 times
Mar 23 13:11:10 irish last message repeated 2 times
Mar 23 13:14:35 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:15:04 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:19:59 irish ntpd[4928]: sendto(64.109.43.141): Invalid argument
Mar 23 13:20:02 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:21:17 irish ntpd[4928]: sendto(80.242.32.5): Invalid argument
Mar 23 13:21:18 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:21:51 irish ntpd[4928]: sendto(212.159.114.45): Invalid argument
Mar 23 13:22:13 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:23:24 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:24:33 irish last message repeated 3 times
Mar 23 13:26:20 irish last message repeated 4 times
Mar 23 13:28:03 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:29:10 irish kernel: input: AT Translated Set 2 keyboard on isa0060/serio0
Mar 23 13:29:11 irish hal.hotplug[8999]: DEVPATH is not set
Mar 23 13:29:11 irish hal.hotplug[8996]: DEVPATH is not set
Mar 23 13:29:46 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:31:10 irish last message repeated 2 times
Mar 23 13:32:15 irish last message repeated 2 times
Mar 23 13:33:36 irish last message repeated 2 times
Mar 23 13:34:54 irish last message repeated 3 times
Mar 23 13:36:04 irish last message repeated 3 times
Mar 23 13:36:48 irish last message repeated 4 times
Mar 23 13:37:04 irish ntpd[4928]: sendto(64.109.43.141): Invalid argument
Mar 23 13:37:12 irish dhclient: DHCPREQUEST on eth0 to 192.168.1.1 port 67
Mar 23 13:38:00 irish last message repeated 2 times
That's just a small snippet. Basically it keeps making the DHCPREQUEST's over and over, as well as the "last message repeated x times," interspersed with "Invalid argument"s. Every time it said "Network is down," that indicates when I manually deleted the linux box's entry off my router's DHCP list and restarted the eth0 device.
I also did not find any DMZ options in my router setup.
Your help already given and any more help is much appreciated!
What model Linksys router do you have? From what I am thinking you should be able to limit the amount of DHCP addresses that your router can give out. I know on my Linksys WRT54GS I gave my network printer 192.168.1.100. I then started my DHCP addresses to distribute from 192.168.1.101 to 192.168.1.104 for my other 4 computers and also limiting the amount of connections that I can have to the router. So maybe you may want to assign your server a static IP within the router and then start your DHCP addresses 1 or 2 above that address.
Quote:
The desktop is 192.168.1.100, and the server box is .101.
Why not assign your server the 192.168.1.100 static, and then start your DHCP at 192.168.1.101. That way if your router or your server reset for any reason you know the only IP address that it will get is the 192.168.1.100. There would be no way that it could change addresses when it doesn't have access to any others.
I have the Linksys BEFSR41. I didn't know it was possible to enable the DHCP server, yet still statically assign IPs under or over the range that DHCP assigns...but I guess that's just me not thinking outside the box again. :-\
Still though, before I try that good idea from Glas, any thoughts on why my now-statically assigned server box still changed its IP address?
Thanks!
P.S. When the server changes its IP address, it shows up on my router's DHCP client list. However, my windows desktop, which has its IP address assigned by DHCP, has never and still does not appear on the DHCP client list, but it still has internet connectivity. Maybe a defective router?...
OK, I am a little confused. I have a Linksys WRT54GS which is a fairly new router. I have Time Warner cable and a SuSE Enterprise 9 server with a couple of XP machines on the subnet.
As I go through the setup for the Linksys Router I see no place to assign a static IP address for a given server. You can assign static IP addresses for DNS which I would not advise since your provider updates these. I see where you can assign the range and port forwarding for http and port 80.
However, there is no where to assign a certain machine a static IP address.
My question would be this. The provider updates the 3 DNS IP addresses, Router IP and Gateway IP addresses. How do you get by this.
My thoughts are you have to configure the server to change dhcp. I also tried port forwarding the entire IP Address range.
Let me give you some detail around the network architecture and perhaps that will help. I am sitting on an internal network that has several Windows machines and a SuSE Enterprise 9 server. They each route either through hard-line or wireless connection through a Linksys Router.
The Router in turn has a gateway IP address, its own IP address and three DNS IP Addresses.
I go to Network Solutions where I registered this Domain and put the Router Gateway Address in their A Records DNS section. So when someone goes to www.hingedmind.com they are routed to the Router.
On the router, I have a port forwarding address on port 80 to the SuSE server (httpd (UDP/TCP)).
I used this with RedHat and had no problems. The got-you’s are pretty obvious. The router is DHCP and if anything changes from the provider (gateways, IP addresses, DNS Servers) I have to go back out to Network Solutions and change the DNS A Entry.
The only time this really happens is when they pull maintenance or an electrical storm hits them. In the past year, only a couple of times.
Yes, I suppose I was a little non-descriptive when I spoke about "assigning a static IP address."
I did not assign the server a static IP through the router - rather, I assigned it through the FC3 box's Network Setup utility (I disabled receiving an IP address from the local DHCP server, which would be the Linksys router). However, the router's DHCP server is very much still enabled, with a current IP address range of 192.168.1.100 through 192.168.1.103. The server is currently .101 (statically assigned on the server itself, not through the router), and my desktop is .100.
What I am inquiring about is why my server has suddenly decided (only recently, too - for months this setup has worked fine without issues) to occasionally abandon its statically assigned address and look my router for a dynamic IP address. Whenever I notice that I can no longer connect to my server via ssh and http, when I have a chance to check I find it is because my server is listed on the router's DHCP Client List with IP address 192.168.1.102. And yet the server itself is still set to statically assign itself the IP address of .101!
Herein lies my conundrum. Tonight I plan on following through with Glas' suggestion to set the server to .100 (statically) and then configure the router's DHCP server to assign IP addresses starting at .101. I hope this will work, and I am still curious as to why my current configuration has suddenly failed.
Thanks for the clarity Magsol,
How are you setting a static on your server? What utility, what file? Did you just turn off dhcp completely on your server?
Also, Linksys Routers require that the router have a unique IP Address and the range be outside of that.
i.e.
192.168.1.1
and the range i.e. 192.168.1.100 - 192.168.1.110
Here is something I am looking into. It might help and it is free. I am not sure about a particular company. Zone edit just explains it well.
Originally posted by Sapient OK, I am a little confused. I have a Linksys WRT54GS which is a fairly new router. I have Time Warner cable and a SuSE Enterprise 9 server with a couple of XP machines on the subnet.
As I go through the setup for the Linksys Router I see no place to assign a static IP address for a given server. You can assign static IP addresses for DNS which I would not advise since your provider updates these. I see where you can assign the range and port forwarding for http and port 80.
However, there is no where to assign a certain machine a static IP address.
My question would be this. The provider updates the 3 DNS IP addresses, Router IP and Gateway IP addresses. How do you get by this.
My thoughts are you have to configure the server to change dhcp. I also tried port forwarding the entire IP Address range.
Basically in order to set a static IP address you just tell the router to start DHCP addresses at say 192.168.1.102 on subnet 255.255.255.0. On the computer you want to set a static IP address on you would manually set it to whatever you wanted, lets use 192.168.1.101 subnet 255.255.255.0. Because this machine is on the same subnet and using an address in the range for 192.168.1.x it will have access to the network. In fact you can still set static IPs from 192.168.1.2 to 192.168.1.100 and still have them access the network. As long as the computers are on the same subnet and have an IP address in the correct range then you have no issues.
Magsol I noticed in your first post that you stated the following:
Quote:
The timing, though, was ironic: I've been busy all weekend configuring my hosts.allow and hosts.deny files, as SSH has been getting a loooot of hammerings, and I wanted to restrict its access to *only* my college's domain.
After looking at this site I am thinking that maybe one of the files you have edited or not edited may be part of your issue. I am trying to do some research on this but it's kinda hard at work when I don't really have access to too many sites due to our firewall .
If you find the answer let us know I would love to know what the actual issue is.
Glas,
When I attempted to set a static IP address on the SuSE server through the Network Address setup I was no longer able to access my domain on the server. It also appeared the router changed the IP address to a different one.
Example:
The Linksys router assigned an IP address of 192.168.1.101 to the SuSE server. I then made that address static. Then when I looked at the router DHCP Clients list, it changed it to 192.168.1.104.
Currently by letting dhcp handle my address I can access the domain (www.hingedmind.com) on the server. However, I cannot see it on any machine on the subnet or outside. I get an error message "Page not Found".
Here are the zone, resolv and host files. Is there something wrong? I have no mail server. Mind is the server name.
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) I had to sit at home and contemplate why on earth my server went down.
so I can't SSH into my server and post the syslog files. However, as soon as I have a moment to sit down at the server I will post what is logged, and hopefully with those and everyone's vast linux knowledge I can figure out what's going on. 
FInally I've had a chance to sit down at the server itself and copy the system logs - here they are:
.
