Networking refers to the technologies and techniques that enable the interconnection of devices and applications allowing them to communicate electronically.

learn more… | top users | synonyms (1)

6
votes
0answers
121 views

Configure Juniper M320 as Ethernet/STM transparent converter

There is Juniper M320. We need to move ALL the traffic from one port to another. Everything that comes to one port goes to another and vice versa. No snooping or any other processing is required. One ...
6
votes
0answers
899 views

Troubleshooting Redmine performance

I've got a Redmine instance (Bitnami Stack) that's unusually slow. Because I'm just trying to get to the bottom of this, I have some theories which I'd like to discuss here. So, if anybody has any ...
4
votes
0answers
53 views

Higher TCP latencies in the latest versions of Linux

In my research group, we recently upgraded the OS on our machines from Red Hat 6.2 to Debian 8.3 and observed that the TCP round trip time through the integrated Intel 1G NICs between our machines had ...
4
votes
0answers
62 views

How can I provide services to an internal air-gapped extranet

Background - "Extranet" We have about a dozen users that are on what I would call an Extranet. It is an air-gapped LAN that is physically in the same location as our primary LAN. We share the ...
4
votes
0answers
57 views

Breakdown Windows Network IO by network adapter and by process

What I'm trying to do is breakdown the Network IO by network adapter and by Process. The goal is to identify which processes are generating the most IO on a certain network adapter. Resource Monitor ...
4
votes
0answers
265 views

some IPs within a subnet not reachable

I'm running 3 Debian-Servers, each with its own IPMI. All IPs are within the same subnet with the same gateway. The problem is, that each server can ping its own IPMI but not the IPMI of the other 2 ...
4
votes
0answers
252 views

IPSec bandwidth between two Pfsense hosts has predictable, variable bandwidth

I have a IPSec tunnel between two Pfsense machines. Both machines are connected to a 100mbps symmetrical connection. The latency between the two routers is ~70ms. I'm using AES-GCM-128 and SHA1, both ...
4
votes
0answers
615 views

TCP connection stuck in SYN_RECV state despite ACK received

My client and server are both internal machines. tcpdump on both client and server show all three parts of handshake are communicated, however netstat on server shows SYN_RECV, and on client shows ...
4
votes
0answers
457 views

Automating Configuration of VMware's vSwitch (OpenStack/libvirt/Nova)

There's a lot of talk now about VMware integrating with OpenStack now. I've noticed that Nova network service is working with VMware's standard and vDS. Deploying a full OpenStack instance is not ...
4
votes
0answers
133 views

Configuring Container with bridges and vlans (server only?)

I have two groups of lxc contianers on a server and want to isolate their network traffic for security reasons. I will be using port forwarding so the containers much each have separate IP's. I know I ...
4
votes
0answers
447 views

snmp MIB-TCP::tcp not showing any usage

I am trying to configure MRTG on all of my servers for making a network weathermap, this requires running SNMP which MRTG gets the information from. So, I installed it on two servers the exact same ...
4
votes
0answers
713 views

keepalived config is not working correctly with virtualbox vms

my keepalived configuration is not working correctly. I have two virtual testing machines (virtualbox) to try some things out with keepalived/vrrp. Bot can ping each other flawlessly (internal ...
4
votes
0answers
2k views

NAT64 configuration with tayga on Debian 6

I'm trying to implement NAT64 with tayga on my server and came to a point where I'm not sure how to proceed. My server is connected via one IPv4 address and one /64 IPv6 address block to the internet....
4
votes
0answers
1k views

Enabling IPv6 with OpenVZ using Proxmox 2.2

I'm trying to enable IPv6 on my Debian nodes (OpenVZ) using venet; my host is under Proxmox 2.2 (kernel 2.6.32-16-pve), and it seems the routing fails. My host correctly pings all my nodes; all my ...
4
votes
0answers
1k views

Jenkins slave fails handshaking on windows

I have a win2k8 machine used as our CI master server (Jenkins) I have various other servers running as slaves The master is listening for slave connections on port 2000 SlaveA - can connect to ...
3
votes
0answers
60 views

How can I identify a rogue IPv6 DHCP server on my LAN?

This will be kind of a long post, but I want to give complete information. I have a home/business LAN with isc-dhcp-server running an ipv4 dhcp server and bind as a DNS server running on an ubuntu ...
3
votes
0answers
31 views

Monitor latency by IP on a bridge-enabled host

Is there a tool which captures packets, measure latency in realtime and display it with some IP filtering options for Windows ? My particular setup : Internet -> Router -> Host Master -> Host Slave ...
3
votes
0answers
28 views

Get floating ip from mmm to work on Tinc vpn on Ubuntu

I've got 3 ubuntu servers connected with a Tinc VPN right now. 2 servers are running mysql 5.6 db's, and the 3rd is used only as a monitor. We're using mmm to do the monitoring and assign a floating ...
3
votes
0answers
221 views

Windows 10 arp cache getting stuck after failed attempts when target machines are offline

After upgrading our development team to Windows 10 from 7, we are experiencing an issue with the ARP cache where a machine has the correct IP-MAC mapping cached, but the type is invalid due to failed ...
3
votes
0answers
81 views

What would cause named to send out hundreds of bogus responses?

My DNS server running RHEL 6.6 is actively sending unsolicited DNS responses to a couple of IP's. By unsolicited I mean that there is no incoming request from the external IP, the DNS server seems to ...
3
votes
0answers
69 views

Inter-connecting 2 Switches on separate racks

I have 2 Dell N4032 switches installed on separate server racks. They are inter-connected on Port 23 and 24. Servers in Rack1 can ping Switch1, Servers in Rack2 can ping Switch2. However, they cannot ...
3
votes
0answers
198 views

Is RSS (receive side scaling) in Windows considered unstable?

When asking a customer to enable RSS in their data center to improve network performance (very high UDP packets-per-sec rate), I was told that they generally turn it off, because after various ...
3
votes
0answers
91 views

Authentication and logging of users for a Wireless ISP?

I have to upgrade a Wireless ISP's (WISP) network. Their current setup consists of a router (Mikrotik RouterBoard 1100AHx2), Ubiquiti Rockets (with sector antennas) for clients, and Ubiquiti ...
3
votes
0answers
196 views

VLAN Communication between Cisco ASA 5510, and VMWare ESXi 5.5

I've having a problem, where my Cisco ASA 5510-v8.2 can't communicate with VM's in a VLAN specific port group. The Cisco ASA is currently sitting in front of a group of VM's that have public IP's. ...
3
votes
0answers
292 views

meaning of 'event_wait : Interrupted system call'

I manage several OpenVPN links. sometimes while the VPN is UP since minutes, hours, suddenly it falls with this message: event_wait : Interrupted system call (code=4) Sep 8 11:13:46 hostname ovpn....
3
votes
0answers
572 views

docker network freezing randomly

Sometimes , all network's of my dedicate server is freezing (ssh also not working). it's randomly repeated. OS: Ubuntu 14.04.3 LTS On server installed docker containers, and i see in dmesg logs: [...
3
votes
0answers
79 views

Does Fast Retransmit and Retransmission Timer work at the same time?

When Fast Retransmit is implemented, if I received packet 1, then I will send an ACK that says I need packet 2, and then if I received packet 3, I will send a duplicate ACK that says that I need ...
3
votes
0answers
155 views

pppd terminated bya SIGTERM in Centos 7 — who's sending it?

Folks, I created a script to keep a persistent "emergency" connection with a 3G modem, so I can access my CentOS 7 makeshift server remotely if the usual network fails. Everything works for a few ...
3
votes
0answers
147 views

Stream IPTV through SSL VPN

I have a question about streaming IPTV through Cisco ASA5510 ssl vpn. My current setup at the moment is: Public - firewall (asa5510) - L3 switch - L2 switch But my iptv source feed is coming to L3 ...
3
votes
0answers
100 views

Add a second bridge to a virtual machine

We have a ubuntu-12.04 host running another ubuntu-12.04 virtual machine with kvm virtualization and bridged network interface on eth4. This network allows the virtual machine access to the outside ...
3
votes
0answers
295 views

Server 2008 R2 NIC in “Unidentified Network” state after connectivity loss is restored

I am having trouble with 2 servers, both with the same symptoms. When they are reconnected to the switch after losing connectivity, they stay in an "unidentified network" state. Only after cycling the ...
3
votes
0answers
262 views

Routing with multiple NICs on debian

I have a machine with two NICs on different network segments, I've set up routing for the different segments. It works if I run all the routing commands manually, but I can't get it to work when ...
3
votes
0answers
410 views

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 ...
3
votes
0answers
575 views

How to convert RJ45 wiring to RJ25

I have a RJ45 cable wiring. I need to use it to connect my printer to network. But the network socket that was available in my printer is RJ25 socket. I thought that i can wired cross cable which is ...
3
votes
0answers
9k views

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 ...
2
votes
0answers
23 views

What is the purpose of a “static LACP” trunk group on HP switches?

I'm in the process of educating myself regarding configuring aggregated links on HP ProCurve switches. Looking at non-vendor-specific documentation regarding link aggregation, the defining ...
2
votes
0answers
55 views

Painfully slow network when routed through Windows 2012 R2

I have a Windows 2012 R2 server with two network adapters, on-board 1G one for the LAN and a 100M D-Link 530T connected to the internet. Internet Connection Sharing is set up on the latter. Client ...
2
votes
0answers
23 views

“Bridge” host-only adapter and NAT adapter in a VM for other VMs?

I'm running Foreman locally in a VirtualBox machine with a NAT adapter and a host-only adapter. I'm running another virtual machine locally which is bound to the same host-only adapter. I can get the ...
2
votes
0answers
21 views

How can I find the docker-machine network adapter name for a docker container?

I would like to introduce network variability into docker containers. Specifically, I would like to be able to run commands such as: sudo tc qdisc add dev vethecb732a root netem delay 500ms 400ms ...
2
votes
0answers
56 views

How can one update BGP ASN on an Azure Virtual Network Gateway?

I have an existing Azure Virtual Network Gateway I'm attempting to reconfigure for use for BGP, per https://azure.microsoft.com/en-us/documentation/articles/vpn-gateway-bgp-resource-manager-ps/ . ...
2
votes
0answers
114 views

How to verify network quality before running important benchmarks?

I have multiple CentOS servers around the world. They all are running a PHP script that tests the latency of some services once per minute. The problem is that sometimes these servers have local ...
2
votes
0answers
34 views

DNSMasq lookup dns for domain by interface

I have DD-WRT running dns-masq to use different name servers for a wireless access point. I want to take this one step further but I can't seem to get it working. My current setup (which works ...
2
votes
0answers
30 views

Allowing outbound internet access with NSX while maintaining micro segmentation

I am getting into the world of VMware's NSX product for the purpose of micro segmenting VM's in the datacenter. That is to say, living in the same network space but not being able to talk to one ...
2
votes
0answers
56 views

Ping problems with two interfaces, same subnet, direct connections to two separate hosts

I have a configuration of a client machine (Ubuntu 14.04.2 LTS) that directly connects to two server machines. The server machines--while on the same subnet--cannot route to each other. Packets must ...
2
votes
0answers
47 views

Slow Login on Network Windows 7

I am trying to troubleshoot an issue where it takes a very long time (4-5 minutes) for users to log on to their computers on a network, and after catching this timeline with the Windows Performance ...
2
votes
0answers
34 views

Windows Credential Manager unexpectedly restores previous state on reboot

After deleting all existing credentials in Windows Credential Manager, and adding a single, new Windows credential by IP with Enterprise persistence, the new state of Credential Manager (with one new ...
2
votes
0answers
38 views

LXC bridge with several IP addresses

While trying to setup a small server with LXC containers, I encountered a problem: I want to assign 4 different IP addresses: 1 address for the host and 3 addresses in a different net for the ...
2
votes
0answers
32 views

Manually specify a tunnel gateway for an IPSec VPN Connection (ASA)

I have currently got several VPN's on-premise that are setup on the outside interface and using the default gateway on the interface as an originating source of the VPN tunnel. Although the outside ...
2
votes
0answers
115 views

Get-WmiObject Win32_PerfFormattedData_Tcpip_NetworkInterface results in 'Invalid Class' error

On of my Nagios plugins to monitor the network load gives me problems on one Windows 2008 R2 server (out of 600). You can download the plugin here: https://github.com/willemdh/...
2
votes
0answers
30 views

network access issue and triage

We have two hosts in same vlan with same route rules. One of them is able to connect to an outside IP while on another I get failed: Connection timed out when testing the connectivity through netcat. ...