I'm looking for a method to assign a default gateway via dhcp randomly depending on ether the last char of the mac being odd or even, or the time the user connects. Is there a good reliable way to achieve this?
View 2 RepliesI have installed dhcp-server on ubuntu. And server is providing ip address to clients (Window machines) but not default-gateway but I have another network in my network and same configuration and same dhcp-server provides every information.
View 5 Replies View RelatedDoes anyone know if you switch networks Where you have your servers hosted on a Non-DHCP Network, and you switch your IP addresses, then do you have to switch change/assign your new gateway address? I'm not sure if its manually assigned? How do you do it? Also what about nameserver resolving?
View 2 Replies View RelatedI need to place an Ubuntu machine on a network where I have a DHCP server which does not configure the Degault Gateway parameter (we don't want ordinary users to browse the internet). Is it possible to leave the machine using DHCP and define the Default Gateway manually (as in Windows XP i.e.)? How?
View 1 Replies View RelatedBack in April I set up a Ubuntu DHCP server and a multiple VLAN network [URL] to migrate our various servers, workstations, etc off the 192.168.1.1 /24 network that everything was on because we where running out of address space. I built out the new network and everything worked great except our AD server would never get an IP address from the DHCP server (static reservation) and even if I set the IP statically on the AD server it couldn't ping the gateway and noone could log in. After several attempts to resolve this, including bringing in outside help, we where never able to figure out what the problem was.
Now 6 months later I have time to revisit the issue without effecting the live network. I used Acronis and imaged the AD server last Friday, cloned it on to another box with the same hardware, and put it up on the new network that's been sitting unused for the last 6 months. Today when I statically set the IP on the AD server (which is what I want) it connects and I can ping it's gateway 192.168.1.1 and all the way across vlans to a test sales agent workstation at 192.168.8.xxx on vlan 800 but only if I statically assign the agents station an IP address. When I try to get an IP address via DHCP it fails as destination unreachable. Nothing has changed in the last 6 months on the DHCP server but now it for some reason can't ping its default gateway 192.168.1.1. All of the config files are the same as they where left from the post linked above aside from the vlan id's used where changed from 1's to 100's (i.e. vlan 3 is now vlan 300) /etc/network/interfaces
Code:
auto lo
iface lo inet loopback
auto vlan100
iface vlan100 inet static
[code]....
why it can't reach the gateway, when I do a tcpdump I can see the DHCP requests come in on eth0 but the server never responds and I'm pretty sure its because it isn't "seeing" them since it thinks there isn't a network connection but I don't know how to trouble shoot to find out where the problem lies.
Back in April I set up a Ubuntu DHCP server and a multiple VLAN network [URL] to migrate our various servers, workstations, etc off the 192.168.1.1 /24 network that everything was on because we where running out of address space. I built out the new network and everything worked great except our AD server would never get an IP address from the DHCP server (static reservation) and even if I set the IP statically on the AD server it couldn't ping the gateway and noone could log in. After several attempts to resolve this, including bringing in outside help, we where never able to figure out what the problem was.
Now 6 months later I have time to revisit the issue without effecting the live network. I used Acronis and imaged the AD server last Friday, cloned it on to another box with the same hardware, and put it up on the new network that's been sitting unused for the last 6 months. Today when I statically set the IP on the AD server (which is what I want) it connects and I can ping it's gateway 192.168.1.1 and all the way across vlans to a test sales agent workstation at 192.168.8.xxx on vlan 800 but only if I statically assign the agents station an IP address.
When I try to get an IP address via DHCP it fails as destination unreachable. Nothing has changed in the last 6 months on the DHCP server but now it for some reason can't ping its default gateway 192.168.1.1. All of the config files are the same as they where left from the post linked above aside from the vlan id's used where changed from 1's to 100's (i.e. vlan 3 is now vlan 300) /etc/network/interfaces
Code:
auto lo
iface lo inet loopback
auto vlan100
[code]....
why it can't reach the gateway, when I do a tcpdump I can see the DHCP requests come in on eth0 but the server never responds and I'm pretty sure its because it isn't "seeing" them since it thinks there isn't a network connection but I don't know how to trouble shoot to find out where the problem lies.
Since I have a new internetaccount, 2 days ago, I have a problem on my server [Fedora Core 8]. I use it as a router.
eth0 is for the internet.
eth1 is for my LAN.
But since my new internetaccount my server uses eth1 for the internet. This is a line from my syslog:
Code:
NetworkManager: <info> Policy set 'System eth1' (eth1) as default for routing and DNS. I killed the NetworkManager daemon and now it works but this must not be the way to do it? Where do I tell my server that I use eth0 for routing and DNS?
I noticed that my internet connection wasn't automatically brought up each time I logged into Fedora so I opened the system-config-network tool and edited my network adapter by checking the box marked "automatically start at boot/login." To my surprise, the connection went down and upon trying to click on the device to let the manager bring up the connection the greyed-out phrase "device not managed" appeared underneath the device name and wouldn't allow me to connect.
Even when I used ifconfig/dhclient to get the connection up nothing happened. I could get the router to assign an IP address through DHCP, pinged a few sites to make sure it was legit, but still couldn't use firefox to browse anything. Seems as if network manager GUI is conflicting with command line attempts to bring the network up. I'd like to permanently disable system-config-network if possible because it's acting screwy!
I'm using Ubuntu 9.10, and I want DHCP to assign an IP address automatically. I can ping my router, and get a reply. I just have no idea how to do this.I'm trying to get my Ubuntu machine onto my Windows network.
View 9 Replies View RelatedI want to setup 1Gbps our lab network and we purchased 'Buffulo Giga layer switch ' with 24ports. Is there a way to tell DHCP to assign specific IP to a particular MAC address of a machine ? We want to use DHCP and whatever the port we use ,it should have same IP ..
View 1 Replies View RelatedI am having some difficulties comprehending some networking concepts relating to multiple subnets and dhcp servers, or dhcp relay servers. I have built home networks many times before, and they have all followed a very simple formula. A single subnet, let's say 192.168.1.0 which is fairly typical for me. My network's DNS server is always also my networks DHCP server. Typically at 192.168.1.1. When a DHCP client broadcasts for an IP over the subnet, 192.168.1.1(My DNS/DHCP server) will not only tell the client what it's new IP is to be, but will also tell the client what it's Gateway server is. This is ALSO 192.168.1.1 for me typically.
In this manner, a client broadcasts for networking information and is given a usable IP, and told to use 192.168.1.1 for most other functionality. Very simple. However, I am uncertain how to expand this to other subnets. Say.. 192.168.2.0.
A: I can use a separate DHCP server for each subnet. or B: I can use a DHCP Relay agent for 192.168.2.0 to pass the DHCP requests to the primary DHCP server on the 192.168.1.0 subnet.
Option A: is fairly straight forward and have had it functioning fine, but it is really B: I want to know more about. It seems somehow much cleaner to me. I prefer to centralize as much of my network provisioning services as possible. It makes it easier to manage TYPICALLY. My question though is related to Gateways and the use of DHCP Relay Agents....
I have a simple system at home where a DSL router is used as a basic dhcp server with one port forward for ssh to a server. I need to allow my daughters, ages 14,12 and 10, to access the net and also email but I want to have complete control and logging. What I'm looking to do is set up the Ubuntu file server I already have on the network to act as a gateway and also add content management and logging as step one.
I also want to add an email server so that all the email comes into the Ubuntu server and then is allowed to be accessed by outlook on their machines after spam/content scanning for valid emails as step two. My question is what, if any, additional software do I need and what options do I have. I've played with dhcp servers at work but never got much beyond ip assignment and network booting so I'm unfamiliar with what is needed for content management and such. As to the email server I've never even played with this at all so I'm completely in the dark as to what I should be looking at to start with. I'm looking for directions, RTFM is fine but right now I'm not sure even WHAT manual/manuals I should be reading.
This is slackware 12. I'm trying to share my internet connection (on eth0) with a computer connected to eth1.
eth0 is 192.168.0.101, eth1 is 192.168.1.100 (different subnets).
But when I try to make eth1's default gateway the same as eth0's, see the error I get code...
I am in a big confusion and searching an answer to calm down my mind.I have my eth0 has following configuration
` ` `
IP 192.168.1.100
mask 255.255.255.0
[code]....
I have installed ubuntu 9.04 Jaunty server from disk. I am connect to my corporate internet. I have put in my http_proxy everywhere I can find to put it. I am getting an ipaddress, gateway, broadcast,etc. My wired is connected. When I try to ping my default gateway it times out. %100 packet loss. I get the ipaddress of the gateway from the (route command).
My configurations on /etc/network/interfaces is correct(I am on another computer so I can't copy and paste) and I even tried updating the drivers for NIC card. I am using a Intel 82567LM-3. I have been working on this longer than I care to admit.
Im trying to achieve the multiple uplinks/provider found on LARTC.org. I have to get the IP addresses from my interfaces (EF1 and EF2) by using a script, but i dont know where to look at for the default gateway from each interface which got their ip address from my ISP.
View 1 Replies View RelatedI have a computer with two interfaces: a fixed connection (eth1) and a modem (ppp0). My goal is to receive UDP packets from both connections concurrently (using the recv() function). The problem is, that the received packets reach the application only when the default gateway is set to that interface's address. For example, if I set the default gw to be in the eth1 subnet, only packets from eth1 reach the application. Other packets are received in the interface (checked using tcpdump), but they seem to be blocked somewhere. The policy defined in iptables is "ACCEPT" for all incoming packets, with no rules at all. I would like to know how to overcome this problem, and anyway how is the default gateway related to incoming UDP?
View 3 Replies View RelatedI have a dual-homed Debian server running squid, but not acting as a router. Simplied network diagram is below - there are other local hops between the gateways and the Internet.
Code:
(eth0 @ 192.168.44.2) <--> (Gateway1 @ 192.168.44.1) <--> Internet
(eth1 @ 192.168.55.2) <--> (Gateway2 @ 192.168.55.1) <--> Internet
Using Gateway1 gives a very fast, but not always reliable route to the Internet. Using Gateway2 gives a slower, but more reliable route to the Internet. The server uses Gateway1 as the default gateway.
I have written a script that pings three hosts on the Internet, and if all three are down, switches the default gateway to Gateway2. This part seems to be easy, but I'd like know if there is a way of routing a ICMP/ping out eth0 to a host, with all other traffic to the host going out eth1, so I can determine if the Internet is reachable via Gateway1 again.
I am realtively new to BGP. I use BGP in my network to advertise my /20 subnet. What i would like to know is what is the point of accepting routes from your neighbouring AS(ISP)?My ISP has given me a default gateway, and no matter what I want to reach on the internet I have to go through that default gateway, so why populate the routing table with soo many routes?also, as i understand it, there are 3 kinds of routes that you can accept, those are full routes, directly connected routes and default routes. What is the diffrence between them and again how do they affect routing since my network only has the one default gateway?
View 2 Replies View RelatedI had a router crap out yesterday. I'd been testing out a new one for the last few days and just reconfigured it to be the main. Took the old one down and everything in my house (Windows 7 PC, XP Files server, Ubuntu PC , windows 7 laptop, android tablet, ps3, etc) seems to be working fine whether it be hard wired or wifi. All except my ubuntu 10.04 laptop. It worked fine before the swap so I can't figure out what's going on.
I'm able to connect to the new SSID without issue but I can't resolve any external names and when I try to ping the default gate way every other packet has (DUP!) behind it. If I'm hardwired I don't get the dup! when pinging the default gateway but I still can't resolve any external names. I have provided the results of an ifconfig and the results of a ping to the default gateway below.
cooley@Quigon:~$ ping 192.168.1.1
PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=2.98 ms
64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=3.04 ms (DUP!)
64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=3.50 ms
64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=5.72 ms (DUP!)
64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=8.09 ms
[Code]...
I posted it on another forum, but could not get response,So I have this cenOS, Ubuntu and windows operating system running on virtual machines.Now I gave them manual ip address, both ubuntu and windows machines can ping the default gateway, but not the CentOS.It should forward 0.0.0.0. to my cisco router address(192.168.5.254),
View 4 Replies View RelatedStruggling to get my Linux server accept ICMP redirects not originating from default gateway. No problem to get it working if the redirects is originating from def gw.I know it's not a good solution security wise, but my network is so cluttered I'm forced to do so.
View 1 Replies View RelatedClient which uses an ISP with a Linux machine (Server 1) with two network cards. Eth0 with ip 1.1.1.2 and gateway 1.1.1.1 these ip's is not public ip's and falls unders the isp's internal range, eth1 with the internal ip range. OpenVPN listen on eth0 for incoming connections. We want to connect to Server1 from external networks. Due to different reasons the isp could not get the routing sorted and give us an public ip on his network. We had to setup another bos (Server2) with eth0 2.2.2.5 and gateway 2.2.2.1 which is public ip's and eth1 with ip 3.3.3.5. Server 2 can communicate via the ISP internal network with server 1. I use DNAT to forward all incoming connections on server 2 to server 1 but the problem I have is that server uses its default gateway for the return packages and does not sent the reply back to server 2. My iptables rules looks as follows on server 2.
/usr/sbin/iptables -t nat -A PREROUTING -p udp -i eth0 -d 196.25.157.135 --dport 1194 -j DNAT --to 192.168.100.170:1194
/usr/sbin/iptables -A FORWARD -p udp -i eth0 -d 192.168.100.170 --dport 1194 -j ACCEPT
I'm using OpenWRT on a WRT54GS. I'm using wifidog in combination with openvpn. For those of you familiar with wifidog, my auth server is located at the other end of an openvpn tunnel and the "wifi dog gateway" is running on the WRT itself. I'm don't really think that wifi dog is the issue. Basically, I'm using openvpn with the "redirect-gateway" option which works well. In this mode, openvpn removes my current default gateway setting and adds the remote openvpn server as the default gateway (as it should). However, overnight, my default gateway on the local network keeps reapperaing (along with the openvpn one as well).
This causes confusion and I don't want any packets (But ovbiously the connection to the actual openvpn server) to go down this local gateway. Why do you think it reappears? Do you reckon openvpn is dropping connection and somehow the normal gateway is being added back? I *could* run a cron script which runs every minute or so with something like "route del default gw xx.xx.xx.xx" (where xx.xx.xx.xx is the default gateway which I don't want to be there) but that is quite messy and means that if I were to ever move the router I would need to reconfigure this and considering that I would like in the future to have many of these wifi dog gateways, this really isn't an ideal option (as every network will have a different default gateway).
I could not able to configure the default gateway ip address onto the system. i use the route command (" route add default gw 192.xxx.xxx.xxx eth0 ") to add a default gateway onto the routing table but it is "disappear" in the routing table when i had restart the service network.
View 3 Replies View RelatedThe router is set up to use a 64-bit WEP passphrase. From what I've read, that means four different hex keys. One of which is meant to be active. I've tried each of the four generated keys, one-by-one. I've also tried putting them all in and activating one, but the syntax seems to be wrong.
I read Alien's Wiki on it, and various other sources. People keep suggesting wicd, but I want it to work with the rc.inet1.conf file first. Just so I know what needs to be entered in order for that to happen. I have a desktop to set up eventually as well, and that shouldn't need wicd.
My configuration file*: [url]
My lspci entry for the wireless card:
Code:
*I've edited this several times since upload, but nothing has worked so I don't think I need to keep it up-to-date. The online file is basic configuration, I believe.
5.10 Breezy configured as machine controller. Works great eth0 is a fixed IP to communicate with controller comms board. Not easy at all to alter - the comms board is hard coded to listen on eth0 for commands.
I can use eth1 as the default gateway and ping google.com, etc. But when I now attempt to communicate with the controller with netcat, e.g.
Code: echo !HH | nc 192.168.1.6 80
I obviously never get an answer since the request is passed via eth1. Using the -g option with netcat doesn't work either. I had a look at iptables but it doesn't seem to be able to do what I want. How I can still use eth0 as my communication port to the controller whilst eth1 is the default gateway?
I've been struggeling with this for a few hours now, googleing and so on trying to find an easy way to just switch which device I want as primary for internet connections. After long battles I'm at a loss, this is the current automatic routing
Code:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
85.225.76.0 0.0.0.0 255.255.252.0 U 1 0 0 eth0
85.225.76.0 0.0.0.0 255.255.252.0 U 2 0 0 wlan0
[Code]...
On a remote system, when all you have is the ssh CLI -
How do you find out the ip addresses for:the Gateway
the DHCP server
the DNS server
Don't need to make any changes.
Which commands will display this info?
I want to use dhcpcd instead of dhclient on Ubuntu. The 'interfaces' man page say: "The dhcp Method This method may be used to obtain an address via DHCP with any of the tools: dhclient, pump, udhcpc, dhcpcd. (They have been listed in their order of precedence.)"
I can't find where to change this default order. I can uninstall dhcp3-client, but this will also remove ubuntu-minimal, which is not a good solution.