Tune tcp connection

how do we tune time_wait tcp connections. since one have syn flood.Solaris 10. do update asap.

Hi,
in Solaris 10, the parameter which controls the time a TCP/IP connection stays open in TIME_WAIT is tcp_time_wait_interval; to check the current value:
# ndd -get /dev/tcp tcp_time_wait_interval
If you want to reduce it, you could (as root):
# ndd -set /dev/tcp tcp_time_wait_interval 30000 [this will set it to 30s]
Please check the relevant manual page:
https://docs.oracle.com/cd/E19455-01/816-0607/chapter4-51/index.html
Thanks,
marco.
P.S.: if that answers your question, please don't forget to mark the thread as answered.

Similar Messages

ASA 5505:Static Routing and Deny TCP connection because of bad flag

Hi Everybody,
I have a problem. I made a VPN site-2-site with 2 ASA 5505. The VPN works great. And I create a redondant link if the VPN failed.
In fact, I use Dual ISP with route tracking. If the VPN fails, the default route change to an ISDN router, situated on the inside interface.
When I simulated a VPN fail, the ASAs routes switch automatically on backup ISDN routers. If I ping elements, it works great. But when i try TCP connection like telnet, the ASAs deny connections:
%PIX|ASA-6-106015: Deny TCP (no connection) from 172.16.10.57/35066 to 172.16.18.1/23 flags tcp_flags on interface interface_name.
the security appliance discarded a TCP packet that has no associated connection in the security appliance connection table. The security appliance looks for a SYN flag in the packet, which indicates a request to establish a new connection. If the SYN flag is not set, and there is not an existing connection, the security appliance discards the packet.
thanks!
EDIT: On the schema, The interface of the main asa is 172.16.18.148...

Check if the xlate timer is set greater than or equal to what the conn timer, so as not to have connections waiting on xlates that no longer exist. To minimize the number of attempts, enable "service resetinbound" . The PIX will reset the connection and make it go away. Without service resetinbound, the PIX Firewall drops packets that are denied and generates a syslog message stating that the SYN was a denied connection.

Opening and closing Multiple TCP connections issues

Hi all I am having an issue with the TCP VI’s and wondering if anyone has experienced this issue.
My application is required to scan 50-100 IP addresses (statically assigned) and discover if an Ethernet device is connect at that IP address. Currently I am able to achieve this by opening a TCP connection and testing the error cluster to determine if a timeout has occurred (no timeout error means Ethernet device available at the IP address). I then ensure that the TCP connections are closed.
The issue I am have is that I require a 1 second delay between the TCP open and the TCP close which significantly slows down the process. Without the 1 second delay the vi successfully connects to the device once then fails to make any TCP connect regardless of the time delay until the PC is reset.
If anyone has any advice I would be very grateful
David Barr
P.S. I have attached a simplified section of code showing this issue
Attachments:
TCP Open close issue.vi ‏15 KB

smercurio_fc wrote:
If I understand you correctly you want the time delay to be 1 second if there's a successful connection....
While I don't have a specific answer for this problem. I want to clarify for him. I believe the issue is, what if all connections ARE there? That means you keep returning a wait of 1 second 50-100 times so It takes 50-100 seconds just to initialize. I think the user is looking for a way to check for valid connections, but do so in such a way that eliminates the need for a wait which is greatly slowing things down.
CLA, LabVIEW Versions 2010-2013

Anyone else having an issue with TCP connections using iCloud for Windows?

Hi,
Before I asked this question, I did wait to see if any related questions came up, but none did, so I submit it now.
On my admittedly older laptop running Windows 7 64b Home, I've run into difficulties with the iCloud for Windows app to the extent that I had to uninstall it.
It would that, as my laptop was running, in the background, iCloudServices.exe would endlessly iterate TCP connections, which, while not actively sending or receiving any data, after some hours would number over 100 instances, taking up resources, and grinding my laptop's WiFi connection to a grindingly slow pace. I ended up, within the app, turning off everything, iCloud Drive and Photos, (I never used bookmarks), but still this would continue to occur.
I contacted Apple Support, explaining what was going on, and they stated they only dealt with IOS and gave me a Microsoft Support number. When I called Microsoft support, I came more and more to the realization that the issue was specifically with the iCloud for Windows app, as that was the only software that was endlessly creating and not closing TCP connections as it was. How was Microsoft supposed to solve an issue with Apple code?
So I called Apple back, whereupon they insisted it was a Microsoft issue. I explained other cloud services installed on the same computer were not having the same issue, it was unique to ICloudServices.exe. They stated they only dealt with IOS. I stated I purchased an iPad Air less than 7 months ago, and was trying to run iCloud in support of that. They again stated they only dealt with IOS, and suggested I again try Microsoft. I asked them if it was reasonable to expect Microsoft to solve issues with Apple code? They said regardless, there was zero support offered for anything having to do with Windows, and all I could do was uninstall the app, which I did, though that did not feel very satisfactory to me. My thinking is, if Apple writes a Windows app in support of their hardware, they should offer support for it.
Anyway, I was just wondering, is this an issue unique to me? or have others experienced a similar issue? I found this issue by opening the Windows Resource Monitor, looking under the Networking tab, and scrolling through the TCP Connections section to find 100+ concurrent iCloudServices.exe instances listed, whereas even Chrome, with multiple tabs and extensions, topped out at around 20.
My one month old Desktop, DYI, sports a solid Asus 1150 MoBo, i7-4790k cpu, 16GB Ram, and an EVGA GTX 970 video card. I list some specs only to illustrate this computer has no hardware issues in comparison to my long in tooth laptop. On this desktop, running Win 8.1 Pro 64b, at least as many, identifiably Apple, background service TCP connections are created even compared to Chrome, regardless of many tabs being open, many extensions, and even some related apps. Adobe does not even come close, though I run the full CC subscription. On this new computer, running Windows 8.1 Pro 64b, there are currently over 50 TCP connections and loopbacks that do not identify themselves, with just a - for the Image, and PID. With the experience on my laptop, I wonder how many of these are generated by Apple software, if not specifically iCloud software?
The frustrating aspect of these connections is they seem in no way active, While the Chrome and Adobe connections can be seen to be transferring data, as long as I am not running iTunes, or so have my iPad actually plugged in, it seems 99% of the time these iCloudServices.exe connections are just taking up ports, neither sending nor receiving any data discernable to me under the Processes with Network Activity, or Network Activity lists, both displayed in the same window as the TCP Connections in the Windows Resource Monitor.
Though I am fairly ignorant as regards coding, it seems as if there is no call to close a connection, very specifically, iCloudServices.exe, when it is no longer needed, and the next time a connection is needed, a new one is opened, rather than accessing the one previously opened. The only other reason I could imagine this might be occurring is if my Norton Internet Security software might mask and/or block the port after a certain time of inactivity.
Anyone out there have any ideas or advice about this? Thanks in advance.

Thanks jared,
I'm still dealing with this issue through Apple. Some time after I posted this, I contacted Apple again. They did start a case up for me, as I was experiencing the same behavior on two different machines, with two different versions of Windows.
So far it remains unsolved. I've logged iClouds for Windows on my desktop, which is brand new, then logged for awhile after completely uninstalling Norton Security Suite, depending on the Microsoft security for some time, and finally logged after I uninstalled iCloud for Windows, restarted, installed a clean download, and connected using a completely different test account, which Apple set up for me. None of this made any difference. Looking at the logs, it seems every 10 minutes, iCloudServices.exe creates a new TCP connection to confirm I'm using less than 5GB on iCloud, (which I am by a good margin, using less than 2GB), it seems this connection is not closed, and when the next iteration rolls around 10 minutes later, a new TCP connection is created. I come very close to having 6 TCP connections created per hour, until I restart my computer. This works out to... 6 x 24 = 144/day.
Perhaps the article you posted will shed some further light on this. I'm thinking seeing the state of the connection through netstats, at the least, could help.
For the last week, I've been putting a hold on further logging, as Apple wants me to create a new user account on one of my computers, install iCloud for Windows there, and log it running in the other account. This however basically means I cannot use my computer for a fair number of hours, and I've been busy enough with work the past week that I haven't the time or energy to afford to set this up and run it. I've had need of my computers too much for the past week.

How do I tune TCP SYN resend/retransmit rate for satellite?

On a satellite internet connection MacOSX (and, I believe, iPhones) have excessively aggressive SYN resend timing.
The existing settings make iTunes and SSL based services (banking, email etc) unreliable and often unworkable.
Plain HTTP (most web browsing) gives the appearance of working because browsers quietly retry.
I have been unable to find a setting in Preferences or sysctl to adjust this. And of course there's nothing useful on an iPhone. It would be helpful if there was some switch for "satellite" or "high latency" networks.
Summary:
When combined with the (common) TCP accelleration in a satellite modem, TCP connections from a Mac over satellite often get reset right at the start when the connection is commencing because of a race condition between the modem's stateful connection proxying and MacOSX's excessively rapid SYN resends.
Workaround:
Running a proxy between the Mac and the modem (in our case, in our firewall) where the proxy runs on a more conventional machine with much slower (normal) SYN resend times seems to work around the issue by making the Mac's connection to the proxy, and the proxy's connection over the satellite connection. Because the proxy's host has better TCP behaviour, the connections succeed.
Detailed problem description and explaination:
At times, SSL connections (HTTPS, POP3S, IMAPS) and other connections receive a batch of RST packets just after setup, leading to connection refused or connection reset by peer. Depending on the app, you get an assortment of errors messages of varying vagueness. iTunes is especailly useless here, just saying an unknown error occurred.
For something that reports the OS-level error you get message like this:
socket error ([Errno 54] Connection reset by peer)
Generally, if the connection succeeds it will stay up. The failure occurs at connection setup time.
From running tcpdumps on my firewall when this is happening, the behaviour is as follows:
For background to understand what follows: a TCP connection is established by you sending a SYN (synchronise) packet to the far end. The far end replies with a SYN/ACK acknowledging the connection. You then send an ACK ackowledging receipt of the SYN/ACK. And then you send and receive data packets.
A successful connection looks like this (you may need to make your window rather wide):
16:47:47.896426 172.16.3.7.50142 > X.X.X..995: S 2233798023:2233798023(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306458055 0,sackOK,eol> (DF)
16:47:48.597903 172.16.3.7.50142 > X.X.X.X.995: S 2233798023:2233798023(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306458755 0,sackOK,eol> (DF)
16:47:48.643500 X.X.X.X.995 > 172.16.3.7.50142: S 0:0(0) ack 2233798024 win 13312 <mss 1321>
16:47:48.644794 172.16.3.7.50142 > X.X.X.X.995: . ack 1 win 65535 (DF)
16:47:48.645639 172.16.3.7.50142 > X.X.X.X.995: P 1:307(306) ack 1 win 65535 (DF)
So: the normal SYN, a duplicate SYN 701ms later (much too early), a SYN/ACK from the far end and an ACK for that from this end. And then normal traffic.
An unsuccessful connection looks like this:
16:48:11.094536 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306481128 0,sackOK,eol> (DF)
16:48:11.797141 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306481827 0,sackOK,eol> (DF)
16:48:12.099393 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306482127 0,sackOK,eol> (DF)
16:48:12.400934 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306482427 0,sackOK,eol> (DF)
16:48:12.702356 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306482727 0,sackOK,eol> (DF)
16:48:13.003581 X.X.X.X.995 > 172.16.3.7.50144: S 0:0(0) ack 2181400206 win 13312 <mss 1321>
16:48:13.005832 172.16.3.7.50144 > X.X.X.X.995: S 2181400205:2181400205(0) win 65535 <mss 1460,nop,wscale 4,nop,nop,timestamp 1306483028 0,sackOK,eol> (DF)
16:48:13.006593 X.X.X.X.995 > 172.16.3.7.50144: R 1:1(0) win 0
16:48:13.007379 172.16.3.7.50144 > X.X.X.X.995: . ack 1 win 65535 (DF)
16:48:13.007778 172.16.3.7.50144 > X.X.X.X.995: P 1:307(306) ack 1 win 65535 (DF)
16:48:13.008437 X.X.X.X.995 > 172.16.3.7.50144: R 1:1(0) win 0
16:48:13.009220 X.X.X.X.995 > 172.16.3.7.50144: R 1:1(0) win 0
A normal SYN, which gets repeated 703ms later, then 302ms after that, then 301ms later, then 302ms later. Then a SYN/ACK from the far end 2097 milliseconds after the first SYN. Then yet another repeated SYN from our end 303ms after the last SYN, then immediately an RST. Our ACK follows (probably already dispatched by the Mac before the RST, but arriving at the firewall just after the RST) and a PUSH with the first data. Two more immediate RSTs come back, presumably for each of these data packets.
By comparison, our BSD firewall resends the first SYN 6 seconds after the original, then even slower. Comparsed to 600-700ms, then every 300ms from the Mac. The Mac's resends interact very badly with sat modem TCP acceleration and sat latency.
There seem to be a few things going on here:
Firstly, something is sending too many SYN packets. There is no need to send repeated SYNs every 300ms. Certainly the best round trip latency over a satellite is about 700ms. The coincidence of the satellite latency and the first resend time probably exacerbates things.
Secondly, sending a SYN _after_ the far end's SYN/ACK has come back seems to elicit an RST packet. I think this is because the modem has established state for the connection because it has seen the far end's reply, and is rejecting what it now thinks is an attempt to set up a new connection using the same ports (forbidden).
Third, this happens more at times of congestion, because the SYN/ACK takes a little longer to come back.
Fourth, the immediacy of the RST packets seems to suggest the RSTs are coming from the modem. So it is probably doing TCP accelleration, and that is producing the RSTs.
There are two problems here:
Up front, the Mac is producing SYNs too often when starting a connection. This exacerbates the problem into something that happens frequently (when it happens at all). This may be TCP "fast mode", but regardless I cannot seem to turn it off.
Second, one could argue that that modem is being overly strict about rejecting the extra SYN. Probably better to pass it through to the far end and let that decide whether to RST it. The modem is doing TCP accelleration (which is fine – it permits better behaviour once the connection is established) but is considering the connection "established" too early. It seems to do it on seeing the SYN/ACK, instead of waiting to see the third packet (the ACK).
I also suspect this happens with plain HTTP as well, but that browsers hide it by retrying connections. The modem is not going to get fixed.
While I think I'm working around this in my firewall now by diverting all outbound satellite connections through a proxy, many users will not have that option, nor any ability to diagnose the issue. They'll just see "Macs don't work on satellite". I'm not alone; there is a scattering of posts on Whirlpool recounting similar symptoms on satellite with Macs.

Hi Peter,
Simultaneous scanning attacks can be achived when the attack is launched with a botnet. At that moment "n" number of systems are launching attack without their knowledge.
Regards,
Anim Saxena
Community Manager,
*Rate helpful post*

TCP connection error when sending MODBUS commands to WAGO 750-881 controller after 113655 bytes of data have been sent

Hi all,
I am new to the world of labview and am attempting to build a VI which sends commands to a 750-881 WAGO controller at periodic intervals of 10ms.
To set each of the DO's of the WAGO at once I therefore attempt to send the Modbus fc15 command every 10ms using the standard Labview TCP write module.
When I run the VI it works for about a minute before I recieve an Error 56 message telling me the TCP connection has timed out. Thinking this strange, I decided to record the number of bytes sent via the TCP connection whilst running the program. In doing so I noticed that the connection broke after exactly 113655 Bytes of data had been sent each time.
Thinking that I may have been sending too many messages I increased the While-loop delay from 10ms to 20, 100 and 200 ms but the error remained. I also tried playing with the TCP connection timeout and the TCP write timeout but neither of these had any effect on the problem.
I cannot see why this error is occuring, as the program works perfectly up untill the 113655 Bytes mark.
I have attached a screenshot of the basic VI (simply showing a MODBUS command being sent every second) and of a more advanced VI (where I am able to control each DO of the WAGO manually by setting a frequency at which the DO should switch between ON and OFF).
If anybody has any ideas on where the problems lie, or what I could do to further debug the program this would be greatly appreciated.
Solved!
Go to Solution.
Attachments:
Basic_VI.png ‏84 KB
Expanded_VI.png ‏89 KB

AvdLinden wrote:
Hi ThiCop,
Yes the error occurs after exactly 113655 bytes every time. The timeout control I would like to use is 10ms, however even increasing this to 1s or 10s does not remove the error, which leads me to believe that this is not the issue (furthermore, not adding any delay to the while loop, thus letting it run at maximum speed, has shown that the TCP connection is able to send all 113655 bytes in under 3 seconds again pointing towards the timeout control not being the issue here).
I attempted Marco's suggestion but an having difficulty translating the string returned into a readable string, (rightnow the response given is " -# + ").
As to your second suggestion, I implemented something similar where I created a sub VI to build a TCP connection, send a message and then close the connection. I now build each message and then send the string to this subVI which successfully sends the command to my application. Whilst not being the most elegant method of solving the issue, it has resolved the timeout problem meaning I am able to send as many commands as I want. So in that sense the problem has been solved.
If you still have tips on how to correctly read the TCP read output, I would however like to see if I could not get my first program to work as it is slightly more robust in terms of timing.
Modbus TCP RTU is a binary protocol, as you show in your Basic VI, where you format the data stream using byte values. So you have to interprete the returned answer accordingly with the Modbus RTU spec in hand. Now what is most likely happening is that the connection gets hung after a while since you do NOT read the data the device sends as response to your commands. The TCP/IP stack buffers those bytes and at some point the internal buffers overflow and the connection is blocked by the stack. So adding the TCP Read at strategic places (usually after each write) is the proper solution for this. Is there any reason that you didn't use the NI provided Modbus TCP library?
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

How to send joystick data over TCP connection

Hi all,
I am a long time Labview discussion forum user for learning, but this is my first time posting a question, I hope somebody can help me!
In the attached VI I am trying to send data from a joystick over a TCP connection. I can send data fine using the TCP examples (in fact the majority of my VI is just a copy of the example). However I am to the point where I do not know how to send all the data necessary (3 axis data, 12 buttons, and the POV data) over TCP. Strings, clusters, and arrays were never my strong suite and converting between them is a nightmare for me.
Basically I am trying to send each axis data (X,Y, and Z), button data (12 buttons), and POV data (the POV data will be calculated to adjust the position of a camera, so the immediate data is not important, I will add functions to add the change in the button movements to write a standing position for two servos [pan and tilt], for which that I will need to send over the TCP connection) over the TCP connection to control various cameras and motors. I don't know if it is posible to send that much data over a TCP connection in one write VI through a string, and also how to separate the string on the other side in order to control the client VI.
Again, the actual TCP communication I get, and can operate fine, just formatting all the data into a string (or whatever is required) so that I can unpack on the other side is the issue here.
Another question I have (not impotant to get the program running just might make it easier on me) is can a TCP server (which sends the data to the client) also recieve data back from the client on the same port ( for example sensor data and digital positions [on,off])? Or do I need to set up two TCP communication loops with the first client acting as the server on a different port than the first, which then sends the data to the original server, which also has a client TCP configuration in another loop? I hope this makes sense...
One final question.....I already have a solution to this but using labview for the entirety of this project would be nice. I use skype to stream 1080p video from a webcam to my computer so I can view live feed. Can labview do this? This would be awesome if so, I am just not sure if the communication protocols in use could support real time (or as close as possible to streaming) for 1080p video.
Thanks all in advance for your help,
Physicsnole
Attachments:
cameraserver.vi ‏24 KB
cameraclient.vi ‏18 KB

Physicsnole wrote:
In the attached VI I am trying to send data from a joystick over a TCP connection. I can send data fine using the TCP examples (in fact the majority of my VI is just a copy of the example). However I am to the point where I do not know how to send all the data necessary (3 axis data, 12 buttons, and the POV data) over TCP. Strings, clusters, and arrays were never my strong suite and converting between them is a nightmare for me.
Well, you cast the axis info cluster to a string, but then you cast it back to an array of DBL. Thatr's not compatible. You should probably cast it back to an "axis info" cluster of exactly the same type. Go the the other VI and right-click the cluster wire to create a constant. Now move that diagram cluster constant to the other VI and use it as type.
Your default ports don't seem to match. You seem to have client and server roles confused. In the sever you create a listener, but then you start sending packets, even though no connection is established. The connection needs to be initiated by the client.
Your client stops the loop the first time a timeout is encountered. Shouldn't that be more permanent? Also, please retain code clarity and avoid unecessary complexities. For example, replace the "not or" with a plain "or" and change the loop to "stop if true"
Physicsnole wrote:
Basically I am trying to send each axis data (X,Y, and Z), button data (12 buttons), and POV data (the POV data will be calculated to adjust the position of a camera, so the immediate data is not important, I will add functions to add the change in the button movements to write a standing position for two servos [pan and tilt], for which that I will need to send over the TCP connection) over the TCP connection to control various cameras and motors. I don't know if it is posible to send that much data over a TCP connection in one write VI through a string, and also how to separate the string on the other side in order to control the client VI.
You can send as much as you want. The casting to/from string is the same as described above.
Physicsnole wrote:
Another question I have (not impotant to get the program running just might make it easier on me) is can a TCP server (which sends the data to the client) also recieve data back from the client on the same port ( for example sensor data and digital positions [on,off])? Or do I need to set up two TCP communication loops with the first client acting as the server on a different port than the first, which then sends the data to the original server, which also has a client TCP configuration in another loop? I hope this makes sense..
The primary function of a "server" is to wait for a connection and then communicate with the client once a conenction is established. An established TCP/IP connection is fully two-way and both sides can send and receive.
LabVIEW Champion . Do more with less code and in less time .

Connect to a printer via TCP connection with wifi

Hi,
what i would like to do, is to connect a printer to the iPhone via wireless.
The printer is in the same wifi as the iPhone and the ip adress is known.
So what i started to to is, to create a SocketConnection with CFStreamCreatePairWithSocketToHost(...). But if i switch of the printer, the inputstream is created too, and is not NULL as expected.
Is this the right approach im using or is there a better possibilty to send strings to my printer using a tcp connection over wifi?
Regards,
Grinarn

Welcome to Apple Discussions!
In the Help menu of the Finder is a little app called Mac Help. Most Apple apps and many 3rd party apps also use Mac Help. In Mac Help is an article called *Adding a printer shared by a Windows computer via SMB/CIFS*. This article is regarding sharing a printer that is connected to a PC over a network however, and not to a router, but may have info useful to troubleshooting. You might also check with your Linksys user guide for info on sharing this printer with a Mac over the network.

How to prevent a TCP connection being closed when the VI that opened it finishes.

Hello everyone.
I am developing an application based around servers and clients communicating over TCP in LabVIEW 2012.
When the server/client opens a TCP connection ,it launches an asynchronosly running "connection handler", to which it passes the connection reference which then takes over all the communcation. This all works fine.
However - I have a situation where a client's connection handler can be informed of another "new" server. I would like it to open the connection (to see if it is still valid) and then pass this connection reference back to the client's main code to spawn a new connection handler. This prevents me locking up the Client's main code with a long-ish timeout if the "new" server is not actually accepting connections.
The issue is that if the connection handler that opened up the connection to the "new" server is stopped, then it appears to destroy the reference that it opened. This means that the other connection handler that was merrily communcating with the "new" server has its TCP communciations closed (I get an Error code 1 on a write).
I have created an example to demonstrate the issue which should be used as follows:
1. Run server.vi - it will listen for a connection on the port specifed on its BD.
2. Run CH Launcher.vi - it will open a connection to the server and pass the TCP reference to an instance of Connection Handler.vi which it launches.
3. The Connection Handler should send data to the Server
4. Stop the CH Launcher.vi
5. The Connection Handler.vi will error.
Any suggestions would be much appreciated.
Cheers
John
Solved!
Go to Solution.
Attachments:
TCP Test.zip ‏35 KB

John_Neutron escreveu:
In my case I have changes the part of the code that opens the TCP connection to a VI that has the same lifetime as the main VI so that any connections that have been opened will only be closed automatically when the main VI stops.
And what are the effects? You are still facing the same problem or closing the connection only when the whole applicaton stops solved your problem?
Regards
Mondoni

TCP connection in labview and C program

Hi there,
I have a server program written in C and running under linux, it
accept connection from client and send series of data to client
through TCP socket. I was using the "simple data client.vi" as the
client.
I tried to send integer number 1, 2,3.. , but the client failed to
correctly decode the data since it read everything as string. I was
wondering if there is a solution to read binary data in labview TCP
connection? I really don't want to encode the double into string and
send it to client through TCP socket in my server program, since it's
not efficient.
thanks !

> I have a server program written in C and running under linux, it
> accept connection from client and send series of data to client
> through TCP socket. I was using the "simple data client.vi" as the
> client.
> I tried to send integer number 1, 2,3.. , but the client failed to
> correctly decode the data since it read everything as string. I was
> wondering if there is a solution to read binary data in labview TCP
> connection? I really don't want to encode the double into string and
> send it to client through TCP socket in my server program, since it's
> not efficient.
> thanks !
>
The string is often used in LV as a general buffer. Type Cast the
string as the appropriate integer and it should be fine. If the integer
has been transmitted in litt
le endian byte order, you will need to use
the Advanced byte and word swapping functions in LV in order to reorder
the integer contents -- LV always assumes big-endian binary format.
Greg McKaskle

Forefront TMG disconnected a non-TCP connection

Hi,
I am getting the following error alerts in TMG
Forefront TMG disconnected a non-TCP connection from 192.168.0.1 because the connection limit for this IP address was exceeded. Larger custom connection limits should be configured for the IP addresses of chained proxy servers and back-to-back Forefront
TMG computers with a NAT relationship.
This error show two msgs for my both dns servers.
My DNS servers Ip addresses
192.168.0.1
192.168.0.2
Please help me out
Thanks

Hi,
How about editing the Maximum non TCP sessions per second per rule setting?
For more information:
http://technet.microsoft.com/en-us/library/dd441028.aspx
Best Regards,
Joyce
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TCP connections alive well after Firefox is closed

According to Sysinternals TCPView, I have several TCP connections that stay open (established) well after I close and exit Firefox, I'm talking 8 hours after. Normal connections close within minutes if shutting down Firefox. I'd post a pic, but there is no option for it so here's a paste (commas instead of tabs):
process/protocol, local address, remote asddress, state
firefox.exe.7108, TCP, russ-l675,gt,rr,com.53713, dfw06s17-in-17.1e100.net:http, established
firefox.exe.7108, TCP, russ-l675,gt,rr,com.54103, 203.30.164.5:http, established
I can (and do!) manually close these connections and they don't come back until I restart FF.
Thanks!
Russ

Yes, but it's been disabled for over a week and this is still happening. Just to be sure, I will uninstall the add-ons. One of these resolves to Australia and the other to a Google server. Am I being watched? This info comes up from the "odd" IP address:
MarkMonitor is the Global Leader in Online Brand Protection.
MarkMonitor Domain Management(TM)
MarkMonitor Brand Protection(TM)
MarkMonitor AntiPiracy(TM)
MarkMonitor AntiFraud(TM)
Professional and Managed Services
Visit MarkMonitor at www.markmonitor.com
Contact us at 1 (800) 745-9229
In Europe, at +44 (0) 203 206 2220
The Data in MarkMonitor.com's WHOIS database is provided by MarkMonitor.com for information purposes, and to assist persons in obtaining information about or related to a domain name registration record. MarkMonitor.com does not guarantee its accuracy. By submitting a WHOIS query, you agree that you will use this Data only for lawful purposes and that, under no circumstances will you use this Data to: (1) allow, enable, or otherwise support the transmission of mass unsolicited, commercial advertising or solicitations via e-mail (spam); or (2) enable high volume, automated, electronic processes that apply to MarkMonitor.com (or its systems). MarkMonitor.com reserves the right to modify these terms at any time. By submitting this query, you agree to abide by this policy.
Registrant:
DNS Admin
Google Inc.
1600 Amphitheatre Parkway
Mountain View CA 94043
US
[email protected] +1.6502530000 Fax: +1.6506188571
Domain Name: 1e100.net
Registrar Name: Markmonitor.com
Registrar Whois: whois.markmonitor.com
Registrar Homepage: http://www.markmonitor.com
Administrative Contact:
DNS Admin
Google Inc.
1600 Amphitheatre Parkway
Mountain View CA 94043 US
[email protected] +1.6502530000 Fax: +1.6506188571
Technical Contact, Zone Contact:
DNS Admin
Google Inc.
1600 Amphitheatre Parkway
Mountain View CA 94043 US
[email protected] +1.6502530000 Fax: +1.6506188571
Created on..............: 2009-09-24.
Expires on..............: 2019-09-24.
Record last updated on..: 2012-04-20.
Domain servers in listed order:
ns2.google.com
ns3.google.com
ns1.google.com
ns4.google.com
MarkMonitor is the Global Leader in Online Brand Protection.
MarkMonitor Domain Management(TM)
MarkMonitor Brand Protection(TM)
MarkMonitor AntiPiracy(TM)
MarkMonitor AntiFraud(TM)
Professional and Managed Services
Visit MarkMonitor at www.markmonitor.com
Contact us at 1 (800) 745-9229
In Europe, at +44 (0) 203 206 2220
Russ

Specify the port in the client in a TCP connection

Hi,
I am programming an application using TCP sockets. I have programmed a server whith a SocketServer(port) and is waiting for client's requests (the server is a public host in the Internet). The client connect to the server by means of the method:
Socket s = new Socket(host, port);
That works correctly, but now I want to specify the port in the client. The client's PC in a machine on the Internet and it has a public IP. I tried to use the method:
Socket(String host, int port, InetAddress localAddr, int localPort)
where localAddr is the local IP of the client' PC (because I cannot know the public IP).
However, it doesn't work this method and the client cannot connect to the server. The problem is that I want to specify the port in the client in the socket TCP connection when I try to connect to the host.
How can I resolve this problem?
Thaks

I want to specify the port in the clientWhy?

Wired port cannot establish TCP connections

I have come across an error that I have so far been unable to solve via google/searching forums.
From time to time, the wired port loses the capability to establish TCP connections. I can ping fine, I can resolve names fine indicating that at least UDP 53 is working. It's impossible to complete a three way handshake for any TCP connection, be it SSH, HTTP, FTP or anything else. This happens randomly after a network connection has been working fine for days. The Internet Connection Wizard claims everything is peachy as it probably just performs a ping to some site.
A reboot does not fix the problem - what does fix it is unplugging the cable, changing to wireless and associating with a network, opening a connection, then shutting down AirPort again and plugging the cable back in. Just replugging without establishing a TCP connection via AirPort does not work.
Is there anything I am missing here? Should I be contacting an Apple Store to talk about repairs/replacements?
Thanks for your time and consideration, if there's any other information needed to make light of the problem, I will post it as soon as I see the request. Unfortunately, I cannot produce the problem at will and have so far neglected running a traffic sniffer to look at exactly what is happening on a packet level - tho "telnet server 80" times out when "ping server" works fine.

Well, I have gotten the FMS on Windows to work via my basic client app (via localhost in the NetConnection call). Taking the same SWF and specifying the external IP of the Windows machine doesnt work.
So I am kind of back to square one.
I made sure that the default Adaptor is bound to any IP (using ":1935,80" in the default Adaptor.xml HostPort tag). So FMS should be bound to all network interfaces.
Just to clarify: FMS is running in "development" mode. Does that mode prevent external connections?

WRT54G2 V1 stops routing after some simultaneous tcp connections

Hello guys, this issue with my WRT54G2:
- when i open more than 2 or 3 browser windows or anything that access internet, it stop routing
- shutdown and power up make it work again (then stops again after some simultaneous tcp connections)
- hard reset dont work
- WRT54G2 V1 Firmware Version: 1.0.04
- please help!

Adjust the MTU size of the router. To determine the value of MTU that should be set on the router, follow the link below.
Determining and setting up the correct MTU size

Tune tcp connection

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