Questions tagged [routing]
the process by which data packets on communication networks are forwarded into the direction of their ultimate destination by routers.
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identify a router that cuts certain port
Is there a way to identify which particular router between me and some server blocks connections on certain port?
I am in a hotel in Thailand, where they have recently changed some settings in their ...
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Do I need routing protocols on a small network?
I have a small network with 10 VLANs, mostly routed via our core layer 3 switch. RIP is enabled on the core switch, but I'm in the process of adding a second router for a couple of VLANs as our core ...
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Why does ifconfig reset the default gateway route?
In FreeBSD, an ifconfig call seems to delete the default gateway route, even when given the same IP-address (e.g. when updating the netmask only). Is it a bug or a feature?
As fas as I remember Linux ...
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Ubuntu defaults to IPv6, should default to IPv4
Ubuntu 16.04.5 with kernel 4.4 used to work as intended: IPv4 is default. Since changing to kernel (hwe) 4.15, it uses IPv6 as default.
It has IPv6 available via Tunnelbroker, broadcasted by the ...
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How to get public IPs on ESXi VMs?
We have a dedicated server with a hosting provider. We are running ESXi 6.0. The server has a single public IP which is currently being used for the management interface. The provider has also ...
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Why is Linux choosing the wrong source ip address
and what to do to let it choose the right one?
This all happens inside an OpenVZ container:
The Host is Debian/Wheezy with Redhat/OpenVZ Kernel:
root@mycl2:~# uname -a
Linux mycl2 2.6.32-openvz-...
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Simple Multihomed Linux Server Issue
I have a Linux server running CentOS 6.4 that is used as an iSCSI target. The server is multi-homed with two NICs, both on the same subnet. iSCSI multipathing takes care of the load-balancing/failover,...
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how do I set static routes in windows domain to all computers at once
Setup, its a test lab and we have some odd requirements
Windows 2012 Server running AD/DNS/DHCP
500 client machines used w/4 physical network interfaces each
2 interfaces are test resources, ...
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Jumbo frames with wireless client
I currently have the following network configuration
Apple Time Capsule (Gigabit Ethernet router)
2 Windows desktop wired with Gigabit ethernet
1 MacBook Pro in wireless N mode
1 iPhone (obviously ...
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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 ...
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OpenVZ multiple networks on CTs
I have Hardware Node (HN) which has 2 physical interfaces (eth0, eth1). I'm playing with OpenVZ and want to let my containers (CTs) have access to both of those interfaces. I'm using basic ...
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AWS: Error accessing the Internet with a custom Network ACL
I've been stuck looking at my screen for about 2 hours trying to figure out why this is not working. I'm building the typical VPC with a private and public subnet and trying to lock it down as much as ...
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How to make connections answer from the same gateway they entered in RouterOS?
I have a MikroTik RouterOS 6.23 device, and my network is as follows:
Router
|
|-- bridge1_LAN (wlan1 + ether1) (192.168.0.210) -- LAN (192.168.0.0/24)
| Here is where computers are. Those ...
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Internet access from private VPC subnet?
My brain is a little bit fried trying to figure this out but I can't seem to get private subnets to connect to the internet to grab updates for example. Basically all I want is web access for these ...
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How to set a static route for an external IP address
I'm putting a new router on our network to help manage our private network connections and to better control routing to the outside. I've decided to simplify this question by removing references to a ...
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Routes bound to virtual interfaces, Debian, and how to determine specifics, after the fact
I've recently begun a new job, and have inherited an existing infrastructure with a lot of issues.
One of the issues is that the previous admin added static routes to some servers, bound to virtual ...
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How can the route between two private IPs go via public IPs?
I'm trying to understand what this output from traceroute means. I changed the IP addresses for privacy but retained the public/private IP range distinction.
traceroute.db -e -n 10.1.1.9
traceroute ...
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Forward differing hostnames to different internal IPs through NAT router
I have one public IP address, one router and multiple servers behind the router.
I would like to forward differing domains (All using HTTP) through the router to different servers.
For example:
...
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How do I add a multicast route in Windows 7?
I have 2 interfaces on my desktop: one in a multicast enabled vlan, that has access to some udp streams, but otherwise unrouted, and one with internet access, but no multicast.
If only the multicast ...
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How to forward host ports of < 1024 to a VirtualBox NAT-connected machine?
The manual says: "Forwarding host ports < 1024 impossible: On Unix-based hosts (e.g. Linux, Solaris, Mac OS X) it is not possible to bind to ports below 1024 from applications that are not run by ...
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Network Drive attached as SCSI Dropping the W/R speed on bigger files
I'm having Network disk attached a SCSI disk
When copying smaller files like 700MB or even 1 GB, speed is high , from 90MB/s to 120 MB, so I'm capable to benefit from 1Gbit network.
But if files is ...
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iptables packet forwarding to one of two gateways depending on origin
Given the following installation:
old router 192.168.1.1 with NAT forward of tcp port 80 to 192.168.1.10:80
new router 192.168.1.2 with NAT forward of tcp port 80 to 192.168.1.10:80
web ...
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New KVM guests cannot access outside LAN
I have a KVM host (at 192.168.0.10) that currently has one working KVM guest (at 192.168.0.12). On attempting to install a new KVM guest today, I reached a problem where the network on the new guest ...
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selective routing through a VPN tunnel
The problem: after establishing an IPsec VPN tunnel all traffic is routed to the remote endpoint, while I only need to route the packets destined to that internal network and still be able to access ...
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IPv6 Neighbor Discovery/Routing Failing for Kernel 3.10
Stupid mistakes led to all of this, read Update 5
Intro
I'm trying to setup a Linux Router (LXC, 3.10.0-123.el7.x86_64) with IPv6.
The provider is Hetzner and I got 2 subnets, one /56 and a /64. They ...
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Specifying Gateway for VPN Connection
I'm not very familiar with networking really, so go easy on me!
I need help enabling Split Tunnelling for client connections to my newly created VPN server. I've un-ticked the Use Default Gateway on ...
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Router advertisement for ipv6 is advertising link-local adress
I have the following situation: I configured a FreeBSD 9.1 machine as the endpoint of a heartbeat SixXS tunnel on a gif0 interface. It works so far, and I can ping6 via IPv6.
I assigned to another ...
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"route add default -iface em1" in rc.conf on FreeBSD
I have two NICs on my FreeBSD server, which are set up like this in rc.conf:
ifconfig_em0="10.0.0.1 netmask 255.255.255.0" # LAN NIC
ifconfig_em1="DHCP" #...
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Policy based routing
I found very good article on load balancing at http://www.diegolima.org/wordpress/?p=36..
I could not implement it though as my requirement is slightly different from pure load balancing.
We have two ...
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RedHat 7: SIOCDELRT: No such process
[user@telco-aa1]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default gateway 0.0.0.0 UG 100 0 0 ...
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openvpn: How to not use VPN for domains with multiple IP addresses
I want to route around openvpn for a specific domain. I have tried:
allow-pull-fqdn
route specificdomain.com 255.255.255.255 net_gateway
But this simply does a DNS lookup of the domain and adds ...
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Make LXC containers directly accessable with ipv6
First off I have a special IPv6 address allocated to my dedicated server, just 1. A ::1/128 one. But I can assign addresses to eth0 (eg ::2/128, ::3/128, etc).
Now I would like to run LXC containers ...
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Possible to have DHCP hand out different DNS server address when using different tunnel?
We have several ASA 5505 deployed. Currently, we have a setup where the local ASA is answering DHCP queries and is configuring clients with two DNS servers: our DR site DNS server (we use AD) and a ...
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Choosing nearest Server across the globe?
i want 3 dedicated servers: in USA, Europe and China. They all run exactly same website. I want to setup them so, that particular user will automatically talk to the nearest in network sense instance ...
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Dynamic subdomain routing
I asked this question over at stackoverflow, but got very few views: https://stackoverflow.com/questions/2284917/route-web-requests-to-different-servers-based-on-subdomain
Perhaps it's more ...
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How do I tell OS X's implementation of Bonjour/ZeroConf which network to use for mdns?
I have four networks on my machine:
192.168.20.0/24 wired (connected only at work)
192.168.20.0/24 wireless (connected only at home)
192.168.132.0/24 VMWare's NAT
192.168.238.0/24 VMWare's host-only
...
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Access services via Cloud VPN from Kubernetes container
I have a VPC network set-up with a VPN connecting to the on-prem network.
Cloud router is used to create routes (BGP) internally and with the VPN network.
One of the projects is hosting public ...
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Routing traffic to two NICs on the same network
I have a few linux test boxes on Scaleway, each having 2x NICs that are all connected to the same network 10.0.0.0/8 but each has its own gateway.
I want to be able to use both NICs (eth0/eth1) and ...
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Load balancing network traffic using iptables
I am trying to load balance traffic from internal LAN on a linux router having two gateways. Initially I went for the iproute implementation which didnt balance the load as expected, reason being that ...
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ping request not forwarded in one direction
Edit: I solved my issue just as I was finishing this insanely long post. I had simply not enable ping reply in my windows firewall which is why I could not ping a computer on network 0 from network 1 ...
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Are Link-Local routes necessary (IPv4)?
I noticed in my routes output in RHEL6 (and most 2.6.x series Linux), for every interface I see the creation of the following route in my kernel routing table:
169.254.0.0 0.0.0.0 255.255....
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OpenVPN server cannot ping client IPs
I have flashed a router at two separate sites with DD-WRT firmware and setup OpenVPN on both. once connected the client can ping computers on the servers LAN however the server cannot ping IPs on the ...
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How do I route between interfaces in PFsense?
I have a PFsense router which divides a single WAN connection into three NAT networks on three interfaces: LAN, OPT1 and OPT2. This allows me to segregate my network so that computers on the OPT1 and ...
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Windows Server 2008 R2 RAS VPN: access server on internal interface ip
short question: I'm usually a linux admin but need to setup a Win2k8 R2 server for a student project. The server is running as VM on a root server and has a public internet IP assigned. Additionally I ...
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What is the purpose of TPROXY, how should you use it and what happens internally?
After reading a bit about TPROXY (e.g at https://www.kernel.org/doc/html/latest/networking/tproxy.html ) I now have more questions then answers. I actually don't even know what TPROXY should do...
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Linux machine unable to send IPv6 packets for five minutes about once per day [closed]
I am operating a router based on a Linux server running Debian stable (Buster). It uses Quagga to speak BGP4 to four peers (one of which sends the entire Internet routing table for IPv4 and IPv6, the ...
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How long is an (accepted) ICMP redirect observed for, and how can I shorten that time?
If a Linux host receives and accepts an ICMP redirect (accept_redirects=1 on the interface in question), how long is this route being cached for and observed? Can I lower that time?
I am asking ...
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Incoming packets don't hit iptables INPUT chain
I'm running a VPN client in a docker container. I'm trying to connect from the host to a web server running in the docker container over port 8080. When I try to connect, I see my incoming packet on ...
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Overcome asymmetric routing while migrating between sets of ISPs
We are migrating from one set of addresses to another set, both /24, and trying to minimize any down time during the migration. Ideally we'd run both for a period of time as we shut down the old ...
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timing issue after route add/delete (route not used)
I have an application that is running a raw IP socket, destination of this socket is governed by routes installed via the 'ip route add' command. These routes can change during the lifetime of a ...