Questions tagged [routing]
Routing (in IP-based networks) is the process of selecting paths in a network along which to send network traffic.
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Route bridge traffic thru a specific interface in my KVM server
My setup is as depicted in the image.
My VMs sit on both virtual subnets. Currently, all traffic from both virtual subnets flows thru ens1 since that is the primary interface with a route metric of ...
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Is it possible to route API with condition in 3scale
I am very new to Redhat 3scale. We have a requirement to route the API request. I do not have any idea whether it is really possible or not. Searched in internet but did not get much idea on it.
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Datagram sent to gateway instead directly to destination host in local network
As this was out of scope for networkengineering, let me ask this here again as this is related to the linux network stack.
I have following setup/situation:
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nftables - Setting destination MAC still sending ARP requests
I'm trying to run DHCP servers behind a private Docker bridge.
I'm at a point where I can reroute the DHCPDISCOVER broadcast packets to the DHCP server behind the Docker bridge and have the DHCP ...
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Route traffic to different IP addresses while using a single outgoing IP
So I have 3 servers, each with his own public IP address. Now I also have a virtual IP(178.x.x.x) that's publicly accessible and it's mounted to one of those servers.
The virtual IP can be moved ...
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Should the routing table only be applied to outgoing packets (not forwarding)?
I am trying to get packets forwarded from device A to device C, through device B. I thought all I have to do is on device A say: packets for C must go to B, and then B knows where where C is so all ...
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Setting up routing between disparate networks across a VPN
I have an OpenVPN server at location A and a client at location B. The firewall/router at location B has routes setup for the VPN network and the local network at location A. The client has IP ...
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Networking - identical routing tables give different results on two hosts
I have the following puzzle:
There are two hosts, with the routing setup as follows:
Host1 (10.40.11.141)
default via 172.27.0.1 dev ovirtmgmt proto static metric 425
10.40.11.0/24 dev bond1.4011 ...
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Respond on the same interface + netplan
I'm unable to send response packets via the "right" interface when switching from ip route to netplan.
The setup:
server - two interfaces
eth1, vlan 101, 10.0.1.2/24, default route, 10.0.1.1 ...
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Fedora 38 - Added a network card for 10G link to a specific system; former NIC got de-configured and there's no new config file
This is on an UPGRADED (not fresh-install - and yes, it matters) Fedora Server 38 box.
After adding a new 10G network card to use as a dedicated link between two systems, the existing, slower-speed ...
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Debugging IPv6 connectivity in fresh Debian 12 installation
Context
I installed Debian 12 in my machine a couple of days ago, and since then I have been facing some issues with (outbound) IPv6 networking. From my investigation so far (having gone through ...
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(I)BGP Asymmetric Routing problem
I have a really strange problem with (I)BGP and asymmetric routing and maybe you can help me.
My setup is as follows:
Router A (running with bird on Linux) ← Internet / eBGP → upstream A / upstream B
↑...
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Access to client local internet and vpn server local network
When I connect to openvpn, I want to be able to access the devices in the openvpn local network and use my local internet. But I can only access local internet and openvpn server machine. Can't access ...
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Second router can't access addresses when a main router routes over it
I have a main BSD router (A) routing some subnets via a second Linux router (B) and everything works fine.
But when I try to access those subnets from the second router, it doesn't work. It sounds ...
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iperf3 with Netplan VRFs
Hi I have 2 Ubuntu 22 machines with 3-3 different VRFs configured through netplan.
When I do a ping -I <source-interface> <destination-IP> everything is working fine, ICMP traffic passing ...
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Service only listens on 127.0.0.1 port 1025. How do you allow any computer on your local network to communicate with this service?
Let me open by saying I have scoured the internet, even companies I purchased the software from and it's been 5 months!! So I am turning to the community as my eyes and brain are bleeding from reading ...
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Route traffic from one IP address through a different interface
I have a local and a remote network. My local network has a router, ubuntu box and TV. The remote network has a router and a raspberry pi. The local ubuntu box and remote raspberry pi are connected ...
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Linux using wrong default gateway
I have two internet connections connected over two different network interfaces (ethernet and wifi). The ip addresses configured are 192.168.1.10 and 192.168.2.5 respectively. When I use
ip route get ...
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tun/tap interface cannot reach the internet
I am trying to set up a NAT: a tun/tap interface tap0, with IP masquerading.
But i cannot reach the internet through tap0 when the default route is through it. Can you help me troubleshoot please?
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Packets are unexpectedly routed to local lo interface
I have a question about routing between different network devices within the same Linux host:
I created a Geneve network device (and this example is not related to Geneve tunnel; it's just that I ...
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Switching between tun interfaces without affecting session
I have two tun interfaces tun1 and tun2 with IP addresses 10.0.0.1 and 10.0.0.2 respectively.
I can make applications use these interfaces by binding them to the IP. For example, I can make iperf3 use ...
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Making a device accessible with SSH from another device over the internet
I'd like to run a Raspberry Pi, on which I'd like to log in with ssh, connected to my router. Then I would like to access it from another RPi, which is connected to another router with physical (and ...
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How to route traffic of docker bridge interface via a VPN interface
I have a VPN interface nordlynx, default interface ens5 and a docker bridge interface br-83e694bd09ad. Currently, the nordlynx interface doesn't have any traffic being routed through it, however doing ...
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Redirecting locally originated traffic with DNAT in OUTPUT chain not working as expected
I am having a dumb, and I am hoping you lovely people can jumpstart my brain.
I am running a service in a local network namespace. The namespace looks like this:
# ip -n ns1 addr
1: lo: <LOOPBACK,...
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dhcpcd deleting gateway
I'm trying to switch from DHCP to static IP by using dhcpcd.
When I switch from static to DHCP I'm configuring that eth0 (which used to have the static address) will also be the one with the DHCP ...
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Why do my TCP connections fail when UDP/ICMP work with policy routing setup?
I have a very nasty problem where I cannot wrap my head around. My goal is to separate my main routing table from the default gateway by putting the default gateway in a separate table (so I can later ...
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In which order is routing of packets defined if VRF and ip rules are defined?
On a system are VRFs, multiple routing tables and rules defined. A local service (SSH) is not reachable via one interface (WAN interface that is in a VRF) while it is reachable from other interfaces. ...
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How to make wireguard exclude port 80 from tunnel
I am running a Debian VPS host
My regular public IP is $A
Under Wireguard VPN my public IP is $B
I have services accessible on ports 4040 and 5050 on $B
I want to access port 80 from $A while ...
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ipset alternative or some kind of smart idea for wildcards
Senior programmer here but hate the linux networking limitations which make things difficult compared to all programming languages.
Practically I need to make policy based routing that allows specific ...
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What is the meaning of linkdown in docker0 Linux Route
I have seen this already, and understand what linkdown means.
However, for the interface of docker0 running on two of my computers, I have two different cases.
Case 1
linkdown with DOWN
$ ip link show ...
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How to configure port forwarding with nftables for a Minecraft server on Raspberry Pi?
Since I'm using a transparent proxy service, I use a raspberry pi as my home router. Its OS is plain Raspbian. Now I'm setting up a Minecraft server on 192.168.2.28, and am exposing it to WAN using ...
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How to configure bird 1.6 router to reject local LAN traffic?
I am setting up CI environment where I have two subnets connected by two peered bird routers.
My current ipv4 config on one of the routers is as follows:
protocol device {
}
protocol direct {
...
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Wireguard routing issues IPv4+IPv6
I'm trying to get a "simple" VPN working between two Linux boxes using Wireguard. Unfortunately, existing tutorials I've found weren't that helpful, because they usually A) only set up IPv4 ...
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In addition to `ip rule`, `ip route`, `iptables`, is there anything else that could affect routing and packet filtering in linux?
Recently I'd like to set CF WARP client on my VPS, but encountered a strange problem. I’m not sure if this is the right place to ask this question, if not I’m very sorry and delete it.
Background:
I ...
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[Mininet/MiniEdit]: Routing doesn't seem to work in case of 2 routers
As a part of an experiment in Mininet,
my IPv4 network has the following topology for two host machines
connected via two routers.
(Running Mininet on an Ubuntu 22.04.02 Virtual Machine.)
N.0.103 ...
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Why would an iptables rule for ANY proto only allow ICMP traffic?
Basically, I have a Linux box (Ubuntu Focal) configured as a gateway:
sysctl net.ipv4.ip_forward = 1 #Enable ipv4 forwarding
iptables -t nat -A POSTROUTING -o ens160 -s 192.168.1.0/24 -j MASQUERADE ...
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How do I setup source based routing on Almalinux 8?
I have a server with 2 interfaces where each interface is connected to a different VLAN with an associated gateway address to route in/out the VLAN. I need traffic that arrives at a particular ...
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IPTABLES - Port forwarding from tun0 to eth0
I have a VPN router (Raspberry Pi with Debian) which connects to the VPN on tun0.
I have a workstation connected to the Pi (eth0) which forwards outgoing traffic over the VPN
#enable forwarding (added ...
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How to route particular IP via one of the OpenVPN clients
I have several fedora servers being gateways for local networks and are connected via tunnels:
server A running OpenVPN server with eth0 192.168.1.1/24 tun0 192.168.94.1 and eth1 1.1.1.1
server B ...
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What is the file location for ip routes in RHEL9?
My route table on RHEL9 looks as below:
root@localhost network-scripts]# netstat -nr
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 ...
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virtual (?) IPv6 addresses
I (can) have a bunch of IPv6 addresses on a (virtualized) server in the internet from my hosting provider assigned in the network which is directly attached (from /64 where eth0 is configured). How I ...
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IPv6 over PPPoE
I have a PPPoE link and some addresses. IPv4 addresses work fine. IPv6 not at all. I found out I had to add +ipv6 in ppp/options. If I ping ff02::1%ppp0 I only get replies from two fe80:: ...
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How to setup a VM Gateway like Whonix but for a generic VPN
I created a linux VM with 3 interfaces: a NAT interface for internet access (eth0 with ip in this range 192.168.84.0/24), a Host-only interface for communication with other VMs (eth1 with ip 192.168....
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nftables anonymous map for ipv6 dnat
When creating a dnat rule, you can specify the following command:
nft 'add rule ip twilight prerouting ip daddr 1.2.3.0/24 dnat ip prefix to ip daddr map { 1.2.3.0/24 : 2.3.4.0/24 }'
And then get ...
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routing table configured with "ip route" part of the "iptables"?
This question is frequent and has already a lot of answers, but I still don't get it. Is the routing configured with "ip route add .." part of the iptables flow? Is the "routing ...
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Curl with random IP v6 from /64 subnet: ndppd, ip neighbour or routing not working
I'm trying to setup random IPv6 proxies pool on my server /64 subnet like this: https://github.com/zu1k/http-proxy-ipv6-pool, but curl --interface 2a05:541:108:26::2 google.com not working (endless ...
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Route a Virtual IP without NAT to a non-virtual IP
How can I route data with a Linux server (Ubuntu) from a VIP to another IP address. I'm currently using keepalived, but it uses a NAT and I don't want that. However, it should be checked via icmp ...
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How do I connect a 3rd computer to a subnet using a port the 2nd computer, so that the 1st computer can communicate directly to the 3rd?
Sorry for the terribly worded question.
I have 3 CentOS 9 Steam computers (PC1, PC2, PC3), and I want to configure it so that PC1 can communicate (ssh, nfs, rpc) directly to PC3. I'm not physically ...
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Access VM from LAN
On a Linux laptop, I want to give access to locally hosted VM (kvm) from LAN.
I'd like to do DNAT to VM.
Network
client <-- LAN 192.168.3.0/24 --> host <-- bridge 192.168.113.0/24 --> ...
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How do you duplicate all UDP traffic on a port range using nftables
I'm trying to get all traffic on port 8000-8900/udp to be copied to another port range, or another virtual device for measuring latency between multiple sources.
I'm aware iptables has a TEE option, ...
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