CentOS 5 Networking :: Unable To Configure Default Gateway Onto The System
Dec 19, 2010
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.
I 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?
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),
in fedora/redhat system I want to add IP address along with Default Gateway and DNS.For assigning IP to eth0 i use the command # ifconfig etho 192.168.1.10 subnet mask 255.255.255.0 upthis remain temporary and when I restart my system it lost the IP address. Well to permanently add IP address in etho I use the file #cd /etc/sysconfig/network-scripts and then use # vi ifcg-eth0 to add IP address and Network Mask. How can I add Default Gateway and DNS permanently in ifcg-eth0 file or there is any other file for it ?
I have a CentOS running. It is important to have my CentOS available when I am remotely connected to a VPN router. I tried to add a default gateway to the VPN router, but after reboot it goes away. How can i put this as permanent?
I have a desktop and a laptop. I have Netgear WGR614v9 Wireless Router connected to my desktop. Since my Laptop is pretty old I also bought a Netger Wireless Adapter for the sme model. Now when I connect the Wireless Adapter I am unable to connect to Wi-fi. I am new to Linux, after googling I ran "lsusb" command and it showed Netgear Wireless adapter and its version. Also in GUI when I open File Browser it also shows the Adapter detected but I am unable to connet the same to my router. Also the blue light on the adapter is not glowing.
I am using Fedora 10. I have a network design like that:
WinServer --- (r1)router(r0) --- (eth1)LinuxPC(eth0) --- intranetPC All netmask is 255.255.255.0 WinServer network is 192.168.1.0/24 intranetPC network is 10.10.0.0/24, gateway is IP of the LinuxPC(eth0): 10.10.0.2
I search in Internet several days to find how to configure the LinuxPC to a gateway. The LinuxPC can ping and connect the WinServer and intranetPC correctly, but the intranetPC cannot ping and connect the WinServer network.
I used the webmin to configure the Gateway. I used the iptables to set allow all connect, than iptables -t nat -A POSTROUTING -eth1 -j MASQUERADE iptables -A FORWARD -i eth0 -j ACCEPT echo 1 > /proc/sys/net/ipv4/ip_forward In "/etc/sysconfig/network" add "FORWARD_IPV4=true"
I am a first time Linux user - though I've Unix and Windows experience. So though I can follow your most tech instructions, I'll need some hand-holding.
Need help getting my wireless network to work on my newly installed Oracle Linux on Dell laptop.
Not sure what wireless card is installed, or it's mac address (though I can boot into windows and get that info, I don't want to - it'll be kind of a let down if I can't fix it all thru Linux).
Install has detected a Broadcom wired card, but not the wireless. Funny thing is that it detected the Bluetooth.
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.
I 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?
I 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?
I 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
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?
I 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.
Struggling 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.
Client 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.
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'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
I installed openSUSE on one of my work system. The network port wasn't working when I was installing, but works fine now (checked in Windows). But for some reason, I am not able to configure the network. I used both Dynamic and Static IPs (both work fine in Windows) but still no go. I am using Yast Control Center for this purpose. I can't even ping the default gateway when I am using custom settings. When I use dynamic settings, it says Unreachable Network.
Recently my motherboard went out, I replaced it and booted centos 5. All went well except sound, video tuners and netoworking. The sound I re-configured, and have gotten tuners working but I am running into trouble with the new network card. The networking setup is;
DSL wireless router/modem IP 192.168.0.1 connected to XP computer through WIFI IP 192.168.0.3. all set to subnetmask 255.255.255.0 and with DNS servers 192.168.0.1 and 205.171.3.25 the XP computer is the only one that supports my wifi card. On wired LAN I share that connection to 4 devices. 3/4 work well, my cent os 5 box will not connect. here are the lan settings:
win xp: IP 192.168.0.60 255.255.255.0 mac 8.6: IP 192.168.0.34 255.255.255.0 blueray: IP 192.168.0.65 255.255.255.0
I have a requirement of switch between wireless network with a single wireless device. First it should be switched to adhoc mode and then after sometime switch to infrastructure mode to establish internet connection. Everything works fine except the gateway settings.
I have used: system("route add default gw x.x.x.x dev wlan0") to set the gateway, where x.x.x.x is gatewayip address. I have used this whenever switching happens in addition to ifconfig command to set the ip address and netmask. But this is not setting the gateway ip address. How to set gateway IP address?
System details below OS :CentoS 5.3 Kernel :2.6.18
I have a network gateway system which runs redhat 7 (2.2.16) Firewall running is ipchains Internal network is eth0 192.168.5.1 External network is eth1 99.99.99.98 (example add)
My problem when I change the static address of the external network from 99.99.99.99 to 99.99.99.98 I am not able to connect to internet. From my preliminary investigation ip is not binded to network card., but I am not sure, is there a way to check binding accurately Below is the ifcfg-eth1 file contents
When a second network adapter is fitted, the boot script fails to configure the default gateway. Here's from /var/log/messages with DEBUG_ETH_UP="yes" configured for the boot script Code: Feb 13 10:22:23 ps1 logger: /etc/rc.d/rc.inet1: /sbin/route add default gw 191.168.1.1 metric 1 Feb 13 10:22:23 ps1 logger: SIOCADDRT: No such process
After boot the same command failed with the same message when done by root logged in via ssh but succeeded when run from the console After removing the second network adapter, the boot script is able to configure the gateway.
EDIT: or not. The problem now seems intermittent Now with only the onboard network adapter the same "SIOCADDRT: No such process" error is logged during boot and the "/sbin/route add default gw 191.168.1.1" command fails at the console too. Am experimenting with disabling the onboard adapter and fitting the NIC.
EDIT 2: definitely intermittent. Just rebooted with no hardware changes; same error during boot and route -n showed no default gateway but "/sbin/route add default gw 191.168.1.1" worked.
And I'm currently working on a new CentOS 5 install I've made on a computer I've got.. So I'm now trying to get that computer to reach my home network through one of my other computers, which have got XP installed. I've configured the XP computer to act as a gateway from one network card to another, and It works with another XP pc, but no luck with my CentOS 5. I used this link [URL] And I configured the correct network card.
So.. the IP of the XP machine is 192.168.1.70, which I have set as a static. So that the CentOS will find it. And I've connected the (fully working) network cable correctly.
What do I have to do?
I have configured the CentOS to recieve an IP dynamically. (dhcp).. Might that be the problem? (well.. one of the problems.. I've tried to set it to static.. ...?)
Is there more to it than this? I mean when I'm working on communication through an XP machine... ?
My company hosts five Servers with CentOS 5 installed in a Data Center. The Data Center assigns a VLAN to each customer so that they can organize customers and also count traffic. The VLAN assigned to my company is in the form 62.103.X.X with a subnet mask 255.255.255.240 so the IPs that we can use in our Servers are 13. The first IP in the VLAN (for example 62.103.1.1) is the Gateway and the rest, that are calculated from the subnet mask, are assigned to servers(62.103.1.2 up to 62.103.1.14).
The problem I have is that we have run out of IPs in our VLAN. We have used all IPs and we want some more. The Data Center can assign new IPs but not grow our VLAN IPs by expanding the subnet mask. So they gave us a new VLAN with some IPs (for example 62.104.X.X with a subnet mask 255.255.255.192) They told me that I had to use as gateway the gateway of the first VLAN 62.103.1.1 and assign the new IPs as usual. So I assigned to one of the CentOS 5 servers the IP 62.104.1.2 and set the gateway to 62.103.1.1. Unfortunately this did not work and we could not establish connectivity to the Internet.Is it possible to assign a gateway outside of the IPs that are in the subnet? Could it be a problem with the VLAN setup by the Data Center?