TCP and IP are two important protocols used in networking today. Due to their importance, the Internet Protocol Suite is also commonly known as "TCP/IP"

learn more… | top users | synonyms

1
vote
1answer
237 views

Millions of TCP FIN-ACK retransmissions blocking traffic on my desktop machine

In a few minutes I have received about 7 millions(!) FIN-ACK packets from IP address that belongs to Google 74.125.133.188 what totally blocked network traffic on my desktop(!) machine. Other ...
1
vote
1answer
88 views

Tcp connection breaking, too fast for serial?

I've been having real difficulties getting a tcp connection to work with my web server. I think the issue might have something to do with the speed or ordering of the packets as the connection seems ...
1
vote
2answers
241 views

Incoming tcp SYNs possibilities

This might be a general TCP question. Can I receive TCP SYN packet on an established connection OR a connection in TIME_WAIT state? Is is possible?
1
vote
1answer
2k views

Determing MSS value on Windows Server

In this Technet article about the MSS limitations of Windows Server 2008, it mentions: After analyzing the network trace collected on the source Windows 2008 Server, we found out that the remote ...
1
vote
1answer
2k views

Best way to calculate optimal subnet masks for a range of IP addresses? [closed]

I thought I saw a tool like this once upon a time, but can't find it anymore... Anyone know a tool that would take a free range of IP addresses (as in start / end) and calculate a set of submasks ...
1
vote
1answer
602 views

Can ranges overlap in ReservedPorts?

The value ReservedPorts in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters contains a list of port ranges to reserve so the system won't assign them to programs dynamically. ...
1
vote
2answers
1k views

Can't connect to a Hyper-V VM from anywhere but the host OS

I have an unusual situation on hand where I'm able to connect to a Hyper-V guest VM from the HOST, but not from anywhere but the host. The VM is running WIn2k8R2 and has IIS installed and Remote ...
1
vote
2answers
7k views

PING: timed out, host unreachable and succes all at once

Is there any logical explanation for this output? I can understand all of the three different results, but all three in one single run of PING? Could my router be defective? I have no internet ...
1
vote
1answer
242 views

Nmap reporting incorrect results from an idle scan

I have a VPS that I was scanning to make sure everything is in check. A regular SYN scan reports that ports 25 and 80 are open (which they should be). When I run an idle scan however, I get back that ...
1
vote
1answer
244 views

Users from my ISP's IP range can't hear my radio stream but others can

I'm streaming a radio via Shoutcast server from a PC in my office and ppl from around the world can hear it in browser or via wmedialayer/winamp, but people from my ISP (including me when I use outer ...
1
vote
1answer
3k views

Why does disabling the TCP/IP NetBIOS Helper service lock me out of GPO?

I disabled TCP/IP NetBIOS Helper and started getting EventIDs 1030 and 1058. This thread said that I'd need to have it enabled. Indeed, when I started it up, the problem immediately went away. My ...
1
vote
2answers
523 views

Static IP for dynamic IP

I have a dynamic IP address. I would like to have a static IP, but Virgin Media don't allow static IPs for residential broadband services, even if you ask them really nicely and offer to pay for it ...
1
vote
1answer
740 views

vmware bridged network interface that is only usable from the guest-system (Windows Host)

I want to make a network interface only usable for a VMware Guest-System, and not for the Host System (the network is considered unsafe, and might be dangerous for the host). Under Linux this is ...
1
vote
1answer
5k views

How to Enable TCP/IP Forwarding in Windows Vista

Is it the same as on XP? http://support.microsoft.com/?id=315236
1
vote
2answers
1k views

Can I add a static route to a VPN network if the default gateway IP is dynamic? (Windows 7)

Can I add a static route to a VPN network if the default gateway IP is dynamic? (Windows 7) This is easy to solve with a permanent route if the default gateway does not change as you can do this: ...
1
vote
1answer
874 views

Can a port be in the listen state and be closed?

Servers running Debian7.7, Mongodb 1.2.0.6-1.1, Nmap6.0 - Thanks for your time. I've user who can't connect to mongodb from his Win7 desktop. He has mongodb installed on it and he's trying to connect ...
1
vote
1answer
3k views

TCP/IP connection to SQL Express works on HALF of the clients in a WORKGROUP

So far I have learned the following facts about Microsoft SQL Server Express, including version 2012, and earlier versions like 2008R2, and 2008, and for the most part all the way back to SQL Server ...
1
vote
2answers
2k views

Connecting to MS SQL 2012 with TCP/IP

I'm trying to enable TCP/IP connections on a SQL Express 2012 database, and it seems as though I'm missing a step somewhere. To enable it, I: Opened SQL Server Configuration Manager Selected "...
1
vote
1answer
162 views

What would cause my SendMail server not to acknowledge receiving a TCP Sequence?

My TCP/IP Stack knowledge is a little rusty so please bear with me.... I have a CentOS 5.7 server with SendMail and am having seeing intermittent timeout issues sending email (particularly larger ...
1
vote
2answers
136 views

Multiple systems with the same IP/subnet

Given multiple systems (embedded devices) on a LAN with a factory-set default IP of 192.168.1.1/255.255.255.0, is it possible to communicate with them using UDP broadcast and to receive an answer for ...
1
vote
2answers
241 views

Solaris VM Experiencing Frequent Timeouts

We are having an issue with all of our Solaris VMs. The issue we're seeing is frequent timeouts when when connecting via SSH or HTTP. It only seems to affect initial connections... when I connect via ...
1
vote
2answers
3k views

Windows Server 2008 R2 IP Address Binding order

How do I set the order of multiple IP addresses all bound to one ethernet interface?
1
vote
3answers
1k views

Windows Server 2008 R2 DNS Server not working?

I have a server running Windows Server 2008 R2 hosting a DNS server, exchange 2010 and is a domain controller. One computer on the network (and domain) can ping the server 25% of the time, also when I ...
1
vote
1answer
1k views

Windows XP/7: custom routing for VPN connection

We are dealing with a badly configured VPN connection from a vendor, which set up the default gateway but doesn't route traffic anywhere beyond their VPN zone. I managed to do some ad-hoc routing to ...
1
vote
1answer
2k views

“Address already in use” error from socket bind, when ports are not being used [closed]

I can not bind (using C or python sockets) to any port in the range: 59969-60000 Using lsof, netstat and fuser I do not see any processes using these ports. Other ports such as 59900-59968 and 60001-...
1
vote
1answer
1k views

TCP RST Reset Every 5 Minutes on Windows 2003 sp2

Recently I had a web developer come to me and ask why he was receiving connection errors in his app that was accessing a sql database. So, I went through my normal trouble shooting steps to isolate ...
1
vote
2answers
2k views

use of tcp_delack_min on redhat linux (kernel 2.6.18)

we're moving from Solaris to Redhat Linux, and trying to duplicate our low-latency setup, that, on solaris, includes the ndd settings related to TCP NO DELAY, and NAGLE ALGORITHM. I got the impression ...
1
vote
1answer
1k views

How can I make WinXP bind to ports other than 1025-5000 for outgoing TCP connections?

(I originally posted a similar question on StackOverflow but readers recommended I post here instead) When you create outgoing TCP connections, most applications let the operating system choose which ...
1
vote
1answer
2k views

Linux IPTables / routing issue

EDIT 1/3/10 22:00 GMT - rewrote some of it after further investigation It has been a while since I looked at IPtables and I seem to be worse than before as I can not seem to get my webserver online. ...
1
vote
1answer
1k views

Solaris TCP/IP performance tuning

I am trying to tune a high message traffic system running on Solaris. The architecture is a large number (600) of clients which connect via TCP to a big Solaris server and then send/receive relatively ...
1
vote
3answers
4k 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 ...
1
vote
2answers
2k views

Accepting a connection on a socket on Windows 7 takes more than a second

Here's what I've done: I wrote a minimal web server (using Qt, but I don't think it's relevant here). I'm running it on a legal Windows 7 32-bit. The problem: If I make a request with Firefox, ...
1
vote
4answers
558 views

Prevent a download to saturate all bandwidth on Linux

In Linux, a single download can use all available bandwidth, so that any other connection can't be started. (e.g. if I am downloading updates, I can't surf the web at the same time) Is there a way to ...
1
vote
2answers
718 views

Sonicwall VPN site unable to communicate with Windows PDC

(First question, please be patient) We have a SonicWall NSA-2400 appliance as our firewall within our primary location. (SonicOS Enhanced 5.1.0.8-17o) Remotely we have 2 sites with Cisco 2800 ...
1
vote
2answers
328 views

Wrong DNS for just one site on development machine

www.superyoink.de is my clients' website. I can access it from any machine except my development one. If I ping it on my development machine, I get 80.67.28.107 - this is wrong. My laptop, next to ...
1
vote
1answer
59 views

TcpTimedWaitDelay is missing in Windows Server 2012

Suddenly my server log shows: An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full And I googled and found these links as ...
1
vote
1answer
60 views

Ephemeral port reuse for TCP connections to different IP addresses

I know that a web server running a website on TCP port 80 can receive TCP connections from many different IP addresses sourced from many different ephemeral ports. Can a client initiate multiple ...
1
vote
0answers
261 views

uWSGI TCP/IP host:port vs Unix socket

We are running a Python WSGI server (uWSGI) and changed to socket file instead of a tcp/ip localhost:port connection. Now our uwsgi logs are full of errors like IOError: write error SIGPIPE: writing ...
1
vote
2answers
44 views

A small puzzle about routing

This is a followup to this question I saw on SuperUser, to which no answer has been provided. A user deleted the second route in his routing table, # ip route show default via 192.168.73.1 dev ...
1
vote
2answers
659 views

TCP timeout for established connections in Windows

I have the following situation: Application (Firebird DB client) on a client computer opens a TCP connection to server on port 3050 Application crash on client, application terminated netstat on the ...
1
vote
0answers
49 views

Corrupted files when downloading with HTTP

With my UMTS connection most archives > 50 MB are corrupted when downloading them via HTTP. If I switch to HTTPS the problem is gone. The problem should not reside in my network, because I have an ...
1
vote
1answer
51 views

high availabilty port forwarding in mswindows

I need port forwarding for a mswindows host, but I need something which can handle more than one target with fail over. There are no end of tools to do this on Linux/Unix (haproxy, balance, pound....)....
1
vote
0answers
18 views

Can a firewall handle packets being sent to it by a network TAP?

We have the intention of examining incoming mails for security purposes. In order to do so we figured out the solution will include: Network TAP - To copy all SMTP traffic to the firewall Firewall - ...
1
vote
0answers
61 views

An already acknowledged data sequence number is coming back as null byte repeatedly

There is a transaction processing server (TP-Server) to which my application (Client) connects to. We are seeing a strange packet sequence where in the TP-Server is sending a PUSH packet with a null (...
1
vote
0answers
106 views

Printer lpd daemon refuses print job if a command's new-line sent separately — bug?

I'm encountering some printer LPD daemons which work fine if the new-line is sent in the same packet as the command, but break if the new-line is sent in a separate packet. Is that a bug in these ...
1
vote
3answers
927 views

Max client TCP connections through a router

I've just been thinking about what the maximum number of client connections would be out of my home LAN to a single server on the internet. My home router is also NAT'ing the connections to convert ...
1
vote
2answers
241 views

How to implement firewall in LAN(out of users' os) like EC2 have done?

In aws ec2, users can set up security groups which works like a firewall, usually, firewall work behind a gateway/nat server, however, I found that firewall in EC2 works in the LAN, too. For example, ...
1
vote
0answers
1k views

NIC Teaming , Multi-Homed, Active/Passive

I'm fairly new to NIC Teaming.. So I apologize if I’m not making any sense while describing this. I’ve, of course, set up plenty of simple Active/Active NIC teams for our servers without any issues ...
1
vote
1answer
1k views

Multiple Homed Windows 2008 Server / Windows 7 Client

I have a small Windows 2008 network, with some Windows 7 clients. The clients are both laptops with docking stations and I would like them to communicate with the Windows 2008 server (for filesharing) ...
1
vote
1answer
558 views

Why won't sql server express 2008 service restart after I enable TCP/IP Protocol?

Whenever I enable TCP/IP connections on my SQL Server Express 2008 database server running on Windows XP SP3, I cannot restart the service, it simply states "The request failed or did respond in a ...