Questions tagged [networking]
Networking refers to the technologies and techniques that enable the interconnection of devices and applications allowing them to communicate electronically.
3,895
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Intermittent Connection Issues on High Traffic Servers
Some brief background: We've been getting reports of very intermittent connection issues from our users. Several times per day, users will have to reload the page they're on due to a connection ...
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FreeBSD 10.1 routing issues
I have FreeBSD based router in my campus.
Trivial configuration for these types of routers: two interfaces, one of them looking to the outer internet, second - to the local net.
In my local net ...
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How to reconnect to the backend with HAProxy
I'm new in working with HAProxy.
I couldn't figure out how to make HAProxy to reconnect to backend that was down and started up back again.
I have a configuration of two backend servers. When they ...
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How to publish hostnames of Ubuntu machines using Avahi
How do you configure Avahi on Ubuntu to automatically broadcast and discover the DNS info for each Linux server on a local network?
I've ran this on my localhost (hostname mylocalhost) and a test ...
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Network Layer 7 Deep Packet Inspection linux solution that isn't a all-in-one distro?
Overview:
I have software that has our Edge/DNS servers hardcoded into them, DNS queries returned from DNS servers are not being masked properly. I need the DNS entries that are returned from BIND ...
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Proxmox vps container connection problems
I have Proxmox on my node server which have ip:5.189.190.*
and I created openvz container on an ip : 213.136.87.* and installed centos 6 on it
The problem:
Cann't connect to container ssh directly
...
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ssh connection freeze after password phase
I'm trying to connect to a server (Oracle Linux 6.3) and after I insert the password the session just freeze.
I checked the audit log and I've authenticated successfully, after I restarted the ...
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Debian, IPv6 is not asssigned to interface
I have a Debian 7 Server with several networks and KVM VMs running configured:
2a01:4f8:191:439b::/64
144.72.132.208/29
The IPv6 Subnet is splitted into /96 Networks to assign each bridge a own ...
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Root denied login if networking down (LDAP environment)
I would like to know why I can't login as root (ssh, sudo or su -) when my LDAP is down or when I have some outage in my network.
How to reproduce the problem:
- Just change your DNS to something ...
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Suddenly cannot reach (ping) remote server on a remote site
We have 2 sites linked together with VPN tunnel (Fortigate 60C devices). On each site I have ESXi server with a couple of VMs. Normally, everything works fine.
Site 1 (S1) subnet is 192.168.254.0/...
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DHCP Server Issuing NAK when servicing multiple subnets
We currently have 3 VLANs setup in our network. On our DHCP server (Windows 2008) we have 3 scopes created for the 3 separate subnets. Our clients can't seem to pull addresses on the subnets, except ...
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Packets not entering FORWARD chain
first of all, this is not an every-day routing issue. The setup is fairly complex, so let me state it before.
I got a router with, lets keep it simple, 3 interfaces. eth0, eth1, eth2.
eth2 is used ...
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Overlapping subnets - VPN
I have Site to Site VPN on Debian box which is setup by rackoon. It works fine, however because subnetworks overlap NAT is used on both ends of the VPN (1.1.1.1/32 & 2.2.2.2/32)
On both subnets I ...
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OpenVPN resets connection repeadly
I have a OpenVPN server installed in an Amazon instance with Windows Server 2008 R2, and there's my client.
First i connect to my VPN
For some reason when i try to connect to my VPN server and RDP to ...
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ksoftirqd process overloads CPU with high-bandwidth and multiple network connections
I got a 10GBit Server with proxmox 2.1
installed. There's an OpenVZ container running with Ubuntu
10.04 64bit.
I can get 200-300MB/sec with wget from data-center internal servers (-O
/dev/null) which ...
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Cannot connect to MySQL on RDS (Amazon Web Services) from my laptop
I'm having some trouble connecting to a MySQL 5.1 server on an RDS instance on AWS from my laptop.
The detailed description of the problem is here: https://forums.aws.amazon.com/thread.jspa?messageID=...
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Why I get different network traffic values from dom0 and from domU?
I'm using Xen 4.0.1 with Linux 2.6.32-5-xen-amd64 (standard packages on a Debian Squeeze system).
From Xen Networking:
For each new domU, Xen creates a new pair of "connected virtual ethernet
...
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4
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collectd:Monitoring server not showing clients
I have setup a monitoring server with the following setup.
<Plugin network>
Listen "0.0.0.0" "25826"
</Plugin>
Now my clients are sending data to the monitoring server(verified through
...
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IP Conflicts from mikrotik router for multiple ip addresses (that it isnt assigned)
I have a point to point wireless connection using two mikrotiks. When I plug the mikrotik into a switch with just my laptop I get an IP address conflict on my machine no matter what IP I am assigned. ...
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iptables SNAT return traffic not reaching client
I have the following design in place:
client linuxserver destination
192.168.160.34 192.168.163.196 192.168.18.1
I can ping server from client ...
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How to mimic "DMZ Host" or "Default Host" NAT funcionality with iptables?
My previous DSL modem had a function called "DMZ Host" (which in other platforms seems to be named Default Host). When you select a computer in your network to be the DMZ Host, it forwards every non-...
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How to assign multiple IPv6 Alias addresses to one network interface
I have an IPv6 Range which i am trying to assign on a centos6 server. I have updated my below files for IPv6 configuration:
[root@test ~]# cat /etc/sysconfig/network
NETWORKING=yes
NETWORKING_IPV6=...
3
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Can't consistently ping both networks of multihomed host
I have a host which is multihomed, eth0 is on 172.31.254.0/24 and eth0.10 is on 172.31.253.0/24 . Obviously eth0.10 is a subinterface on vlan id 10.
From this host I can succesfully ping hosts on ...
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Running both ADSL2+ modem and LAN connection over a single Ethernet line?
We have two office locations, A and B.
We have two ADSL2+ lines at both A and B, as well as a switch at both sites.
At site A, the ADSL2+ line is plugged into a system running pfSense 2.x, that's ...
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Slow access to files on network drive from Hyper-V guest
Windows Server 2022 with Hyper-V on Dell PowerEdge R550.
On Hyper-v there is a Windows Server 2016 guest which is an Active Directory Domain Controller.
Accessing a file from Windows Server 2016 is ...
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How to debug curl when netcat works?
The following cURL command hangs:
$ curl -v http://1.1.1.1/*
Trying 1.1.1.1:80...
* Connected to 1.1.1.1 (1.1.1.1) port 80
> GET / HTTP/1.1
> Host: 1.1.1.1
> User-Agent: curl/8.3.0
> ...
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Slow NFS performance on multi-user systems
We're using mounted NFS drives on multiple multi-user Ubuntu systems. From times to times, the NFS read and write performance is very slow, taking many minutes to perform a simple ls operation. On ...
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DHCP unicast packets processing in Linux
I'm trying to catch and process (in 3rd party analytics app) DHCP packets from ERSPAN session, but cannot do this. There is PHY interface which receive ERSPAN traffic and erspan-type interface to get ...
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1
answer
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Unable to establish link between Mikrotik router and Mellanox NIC
I am trying to establish a 25 GbE link between Mikrotik CCR2004-1G-12S+2XS router and a server running Windows Server 2022 with Mellanox NIC (MCX512A-ADAT).
For cabling, I tried using the official ...
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No network access from MacOS terminal
A colleague's Macbook refuses to make any remote connections from the terminal. For example:
macbook-pro% rvm install "ruby-3.2.2" ...
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Installation of dual stack k8s cluster on node with only IPv6 network
I am trying to understand if it is possible to install a dual stack k8s cluster on nodes with only IPv6 network. Nodes don't have any IPv4 addressing. I am using kubespray to install k8s cluster but ...
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Linux ports become unavailable
We have some Ubuntu 18.04 servers with hard-to-diagnose problems that have some similarities. The servers run a hosted VOIP PBX service with various component applications.
Kamailio occasionally ...
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How does a vpn route all traffic through it's tunnel but allow it's own traffic to go over the internet
TL;DR
I want all outgoing traffic from my system to be routed to a tun0 device, wrapped with DNS packets and then sent to the internet, but the DNS packets also gets routed back to tun0 device.
...
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468
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How to check CPU utilization of Linux kernel networking?
I implemented a "bridge" on my home network where I've got
ISP <--1Gb Internet--> Router <--1GbE--> Linux Workstation <--40GbE DAC/Fiber--> Windows PC
by following this ...
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1
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Ansible 'ping' fail - 'session request sent', but 'read header failed: Broken pipe'
I'm a newbie at Ansible and my goal is use this tool to configure Moxa switches by SSH interface. I'm able to connect via SSH from my Ubuntu PC without problems:
[email protected]'s password:
...
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1
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OVH IPv6 on ESXi -> pfSense -> VM setup
Currently setting up some VMs on an ESXi host on an OVH machine. I have two IPv4s on OVH including a virtual MAC address as needed by OVH. One IPv4 for the ESXi host itself, another one for the ...
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Use ip6tables to forward traffic to setup DNAT/SNAT to link local address
I'm trying to use a raspberry to connect a terminal device to a VLAN. Basically I need to reach a device (that I cannot directly connect to a VLAN) remotely.
My idea is to connect the device (via eth) ...
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What's The Difference Between Rate-Limiting and Throttling?
I keep hearing the terms used interchangeably, but is there an actual difference?
In this article they mention:
Rate Limiting and Throttling policies are designed to limit API
access, but have ...
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Should I use an existing WireGuard connection as basis for a K8S CNI plugin?
I'm setting up a Kubernetes cluster, where the Nodes are distributed across different networks. Additionally, all Nodes are part of a WireGuard network. Each Node therefore has 2 IP addresses, one ...
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Correct F/UTP cable installation
I've read a lot of things about shielding in twisted pairs cables and I feel like it's a controversial topic. I want to know the correct method to connect two devices using a F/UTP cable.
Assume a PC ...
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ifup eth0 - /etc/network/if-pre-up.d/iptables exec format error
I am currently unable to bring eth0 up again at my Debian 10 vServer after my hosting provider was fixing some issues and restarted my container.
sudo service networking status will output:
ifup[378]: ...
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SSH connection is broken down when wireguard is connected
I am going to connect to the vps by ssh and connect to the wireguard vpn service on it.
But as soon as I execute the wireguard client, ssh connection is broken down.
Of course I know this is because ...
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Why can I get on <1G on my 10G Network?
I have 4 CentOS 7 boxes with SuperMico 10000BaseT NICs plugged into a Netgear ProSafe XS712T switch with Cat8 cables. Switch is all default settings, but shows NICs at 10G Full. NICs are configured:
...
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Unable to connect to ESXi NFC (902) from one particular LAN segment
I have an issue with Veeam Backup & Replication backups failing because the Veeam proxy servers cannot connect to the ESXi host over port 902 (NFC). The ESX hosts are on VLAN65 and the Veeam ...
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No responses to ARP requests
One of my server's physical interfaces eno3 is part of a bridge br0. There is also one LXD machine attached to this bridge (nictype=bridged, parent=br0).
Sometimes ARP stops functioning completely.
If ...
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my bridging configuration on freebsd 13 ins't properly configured because any bhyve VM based on Ubuntu 21.04 and Windows 10 can't connect to internet
I've configured the bridging and the tap interface on freebsd 13 because I want to boot and use a bhyve VM based on Ubuntu 21.04 and Windows 10,but unfortunately,after several readings and help ...
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How to properly clone packets with tee?
Trying to understand the TEE module of iptables.
Intend is trying to clone and send the same packet to 2 IPs
Tried the following
iptables -A INPUT -P tcp --dport 2003 -j TEE --gateway IP1
iptables -A ...
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How to manually setup Whonix networks for QEMU?
I would like to run Whonix directly using QEMU instead of using libvirt and I want to manually setup internal and external network. Using libvirt I would need to run those commands:
virsh net-define ...
user779356
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Static IP - Destination Host Unreachable
I'm a newbie to system administration. I've installed remotely a Dell server using iDRAC interface. Server's ip is 200.159.243.146 and everything is fine with it.
Using this interface I've installed ...
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MySQL server won't accept remote connections
I have a server (CentOS 7) running a fresh install of MySQL server (14.14 Distrib 5.6.51) with a dummy database, and I can't connect to it from a remote computer (both remote server and local computer ...
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