Tagged Questions

1
vote
1answer
33 views

iptables: Allowing only established outgoing connections like DMZ

I want to simulate a DMZ like scenario where server1(inside DMZ, 10.1.1.0) should be able to respond to any incoming connection and cann't make a new outgoing connection on its own. I would ...
0
votes
1answer
296 views

Setting up routing in CentOS 6.4 as a router/DHCP server with two nics

I am stumped about how to setup centOS 6.4 to route packets. |Local Network| -eth0- |CentOS 6.4 box| -eth1- |Internet| The centOS box has a dhcp server running. Currently it is handing out IP ...
1
vote
2answers
309 views

Bridge networking static IP's to virtualbox VM's

Ok, so I have a dedicated server with the static primary IP address 89.200.xx.xx, it's running 3 VM's in virtualbox (all Centos 6 as is the server) and I have 3 other IP's that I want to assign to the ...
2
votes
2answers
73 views

Migrating an ip address alias from one server to another

I run: /sbin/ifconfig eth0:10 xx.xx.xxx.221 netmask 255.255.255.224 down on box1, and on box2: /sbin/ifconfig eth0:10 xx.xx.xxx.221 netmask 255.255.255.224 up Both boxes are located on the same ...
0
votes
0answers
55 views

dom0 with guests on two different subnets

I have a Xen dom0 running CentOS. It has an assigned IP address from a /29 block. There are guests with addresses also from the same /29 block. The dom0 is using bridged networking. Everything is ...
-2
votes
1answer
782 views

PPTP IPTables routing issue

PPTP connects just fine to the radius server PPTP modules are loaded into the kernel PPTP connects fine to the pptp service Question: How do I get the PPTP to connect to the internet? IPTables: ...
8
votes
1answer
844 views

CentOS, two nics eth0 eth1 with different subnets aren't reachable outside VLAN/subnet

I am having an issue with a CentOS 6.3 box. We have two NICs (eth0 and eth1) in the server which each have an ip from a different subnet assigned, let's say eth0:192.168.1.2/24 (gateway 192.168.1.1) ...
0
votes
2answers
104 views

IPv6 static routes

I am looking to configure a few hosts with IPv6 on my network. The router (running CentOS 5) is configured with an Hurricane Electric (HE) tunnel which works fine on that host. However, I would like ...
-1
votes
1answer
49 views

Combat server downtime by duplicating server and re-routing when main server is down [closed]

I have a CentOS server which at times either crashes or gets attacked with DDOS. At the moment I have an off site backup which is filled up with 1.7TB of data. I'm currently paying as much for the ...
0
votes
1answer
353 views

centos 6.3 kvm external ip forwarding to guests

I have a centos 6.3 server with kvm installed. The server has 4 external ips and one NIC. 176.9.xxx.xx1 176.9.xxx.xx2 176.9.xxx.xx3 176.9.xxx.xx4 I use the following configuration ifcfg-eth0 as ...
0
votes
1answer
119 views

Routing over a VMware centos server running Cisco VPN

I need help routing over a virtual server to a IPSec tunnel. I have: Mac OS laptop (10.20.4.0/24) VMware Fusion Centos running on VMware (192.168.141.0/24) that has a Cisco IPSec tunnel ...
0
votes
1answer
420 views

openvpn tunnel- tunnel is up but issues with routing

I am having trouble with a site to site tunnel. Both routers are centos based routers. Router A is the server, and router B is the client. The VPN tunnel is established. From router B, I can ping ...
2
votes
2answers
2k views

second ip address on the same interface but on a different subnet

Is it possible in CentOS 5.7 64bit to have a second IP address on one interface (eg. eth0) - alias interface configuration - in a different subnet? Here is the original config for eth0 more ...
0
votes
1answer
394 views

Multihoming with iproute2 and multiple VLANs

I'm currently in charge of setting up our office's Linux router. We've been operating with two VLANs (one for data, one for voice) and a single WAN connection. Recently, we've had issues with our ...
3
votes
2answers
529 views

Basic networking: Centos Server Router + Ubuntu Client setup.. unable to access outside world from client

I am trying to set up my Centos Server with two NICs as a router. eth0 is connected to the outside world and eth1 is connected to an Ubuntu client. Here's eth0 on the server: DEVICE=eth0 ...
0
votes
2answers
325 views

How to route traffic from multiple ips (with single NIC) in a server linux

I have server(CENTOS) with one NIC and it has multiple ip addresses let's say my ips are 192.168.1.10, and 192.168.1.11. I would like to route route traffic from both ip's. I am struggling solve ...
0
votes
2answers
621 views

3 IPs on 3 NICs with 3 Gateways - #3 not responding to requests - routing to wrong port?

I have a CentOS 5.5 server that is using 1 of the 2 on-board network ports (eth0) and 2 PCI NICs (eth2 & eth3) - each has it's own IP on a different subnet with different gateway on a different ...
0
votes
1answer
491 views

How to Route Internal Traffic on a 2nd NIC without a Default Gateway

The actual deployment of this will happen with a larger number of servers, but for purposes of simplicity, let's assume the following is my future setup (I need +4 reputation to embed images, so ...
1
vote
1answer
972 views

ip routing on cent os

I have a web server with installation of Cent OS 5.6, cPanel/WHM. Currently the server have 2 ethernet and the configuration for both is listed below: ...
0
votes
1answer
165 views

Internet Access via CentOS box used as Router

I am having problems getting my network to play nice, despite it working previously. Here are the main system details; CentOS box as a router / firewall (firewall currently disabled while I get the ...
1
vote
3answers
1k views

help with a static route on centos 5.6 please

I currently have a machine connected to a LAN and to the internet working fine. I now got a dedicated connection to a remote office and must create a route from my machine to specifically 1 machine on ...
0
votes
1answer
613 views

Trixbox CentOS Default GW Problem (Multi-homed server)

I'm having an issue with a CentOS trixbox server which is dual-homed (one private facing NIC [eth1], one internet-facing NIC [eth0]). I can't seem to get the default gateway to set properly to our ...
3
votes
3answers
1k views

Dead gateway detection on linux

I have to setup dead gateway detection on a linux box with three network interfaces. The only guides I have found so far on the topic imply patching the kernel, which we are not very keen to do. Is ...
1
vote
2answers
914 views

Redhat / CentOS Static Routing Problem

Looking for some advice, I'm pulling my hair out trying to figure this out! Running Redhat (CentOS) with fairly normal configuration and I've disabled the firewall for now. I have a web server which ...
4
votes
2answers
8k views

Where route to 169.254.0.0 comes from?

Running CentOS 5.4 Why do I have route to 169.254.0.0 although it does not appear in Network > Ethernet Device > Route configuration dialog? Destination Gateway Genmask Flags ...
1
vote
3answers
2k views

how do i change outgoing ip address for server centos

I need to make sure my clients outgoing ip address uses the dedicated ip they are assigned. For example, site123.com has an ip of 123.123.123.2(eth0:1) (resolves fine when incoming) but it is using ...
2
votes
7answers
1k views

Networking issues with Linux server (CentOS 5.3)

I have a Linux server hosting our bug tracking software (CentOS 5.2 Kernel 2.6.18-128.4.1.el5) that I have having some strange network problems with. The machine is configured with two NICS, one for ...