Whenever I call a specific RPG program my Personal Communication client gets disconnected. It was working fine last day but today it has strange behavior rest of the AS400 system is working fine. What could be the reason?
Thanks
This was happening due to some network slow response. As the program which I was calling was eating up network resources that's why my Personal Communication client was disconnecting continuously. One that day overall network was slower. It didn't happen afterwards.
Related
I'm using VxWorks 5.4 and attempting to connect to a server via TCP. A server which I'm going to be sending logs to, but for some reason at boot it fails or takes even up to 6 seconds - and is blocking the continuation of the task that the connection attempt was made in, which obviously is a big no no.
I have checked if the problem is one the server side by making a simple c program in windows that would connect to that server, and it takes no time at all (milliseconds).
I have "solved" the problem by making a task that would attempt "connectwithtineout" every 1-2 seconds and it does work (initiates the connection after around 2 fails in around 20ms), but I don't really like this approach and would have liked to initiate the actual connection when whatever I need that I'm missing is there and up instead of checking if I can connect every time.
After trying to investigate what the issue could have been, eventually the problem was about how a session is being closed between my system and the server.
You see, when you have a client running on some app on your windows/ or whatever other system, when you shut it down, it goes through some processes that close the session properly.
That is not the case in my system where to close it I essentially unplug the wire - thereby not having my system go through a shutdown process that involves properly closing the session.
After the system is up again, the connect function cannot be performed because my system tries to make the same session as the "dead one" which the server thinks is running.
Solving the problem was easy from the server side, just have a keepalive functionality - if your system doesn't respond for a while that you decide, close the session.
I am using java mail 1.6 on Kubuntu Linux 18.04. It all works beautifully. I am connecting to an IMAP server, getting email, etc.
But there is one thing that is causing me grief.
After I close my laptop for a short period of time (so the laptop is probably sleeping), and then open it up, java mail keeps working just fine.
However after I close my laptop for a long period of time (overnight, so the laptop has probably suspended), and then I open it open it up, two things happen:
idle stops working (I have coded this with both IdleManager and
folder.idle, and get the same issue)
when I close a Store or a Folder javamail simpy hangs.
I am guessing that somehow the TCP connection to the IMAP server has died, or maybe I have some timeout set wrong.
I would post code but its buried in a large application, and I am hoping someone has seen this issue before and it has a simple fix.
gym
What I'm doing
I'm implementing a websocket server on a stellaris board as the title says. At the moment I'm able to establish connection to the client and send a few frames.
The way I'm implementing the websocket
The way I'm developing it is something like a master slave communication. Whenever the client sends a string, the server decodes it and then answers. At the moment I'm simply responding to a character 'e', which is designed to be just a counter. The thing is that I implemented the websocket on the client side to send 'e' whenever it receives a message and then displays the message on the page.
The problem
The problem is that it does about 15 transactions and then I can see the communication being re-transmitted from and to the stellaris board and then the communication closes. After the connection closes I noticed that that I can't access any other page on the board. It simply doesn't respond anymore.
My assumptions of what may be causing it
This lead me to believe that the transactions are being too fast and there may be an implementation bug, lwIP bug or hardware bug (I'm using the enet_io example as base).
My assumptions on how to fix it
After seeing this I can imagine that what I need is to control the string being sent to the microcontroller so that it sends once a second, or maybe even less, because at the moment it was doing something like 1000 transactions per second and sometimes more.
The question
So ... after my trials I still have a few questions that need to be answered. Do websockets need this kind of relationship? Where client asks and server serves? Or can I simply stream data from the server to the client as long as the connection is open? Is my supposition that slowing down my rates will work?
Do websockets need this kind of relationship [request-response]? Where client asks and server serves? Or can I simply stream data from the server to the client as long as the connection is open?
The Websocket protocol doesn't require a request-response model (except for the connection establishing handshake).
The server can stream data to the client without worrying about any response or request from the client.
However, it's common practice to get a response or a ping from a client once in a while, just to know they're alive.
This allows the client to renew a connection if a message or ping fails to reach the server - otherwise the client might not notice an abnormally dropped connection (it will just assume no updates are being sent because there's no new data).
It also allows the server to know a connection is still alive even when no information is being exchanged.
Is my supposition that slowing down my rates will work?
I guess this question becomes less relevant due to the first question's answer... however, I should probably note that the web socket client (often a browser) will have limited resources and a different memory management scheme.
Browsers are easy to overwhelm with too much data because they often keep references to all the exchanges since the page was loaded (or refreshed).
This is especially true when logging events to a browser's console.
I would like to send a message, or something can be an advise from a pc to an another pc (only one, or at the most 2), the latter is powered off.
The pc which should send the message is a windows server 2003 os, instead the pc which should receive the message is a windows xp os.
The two machines are in the same domain and they work together through an ingres database.
The message will be sent at night, because there is an ingres database back up procedure that runs at night when my pc will be powered off, but when in the morning i will be at work I would like to read this message as a net send message, or something like
Unfortunately the net send command is disabled in our network, so I can't use it, but i'm looking a way for sending this message.
Have you any suggestion? thank you
Use age-old simple file based messaging.
Store a message in a specific file in the server and write a simple application which runs on startup on your machine to read it and display it.
And this is apart from rerun's great suggestion :)
There is breaking new technology available called email.
Is the machine powered off or in standby?
If if is in standby, then I will defer to someone who may have a better idea of how to get wake the machine to wake up programatically(sp?).
If it is powered off then read on...
If you have access to the machines bios settings, then I would suggest scheduling a power on event in the range of the time before the backup normally completes.
Then it is a matter of receiving the message and optionally shutting back down afterward?
If you are unable to change the bios settings, then does the machine "power on after power loss?" If so, get a programmable timer from the nearest retail store and power off before leaving at night and have the timer set to power on before the time the backup could reasonably be completed.
This is not really a software solution per se, but your problem does seem to be mostly hardware related (with the power off requirement and all...)
I'm running a game website where users connect using an Adobe Flash client to a C server running on a Fedora Linux box.
Often users complain about disconnects. Usually they're "Connection reset by peer"-disconnects.
Is there any way to make the connection more stable or does it all depend on the route from the user host to my server?
One thing I tried is to make it more stable by sending PING in clear text every other minute to avoid timeout problems.
Anyone got more ideas?
You are not exhausting the number of socket/memory use/cpu that the server process is given on the server, are you?
Do check with ulimit.
Also, if possible try to trace the error message in the source code (when a RST packet is sent--), i.e. when a send() or accept() returns an error value. In such cases print a debug message into the logs; if you really fancy debugging it do a simulation of the server:
run it into debug mode on a separate machine (possibly a clone of the server)
simulate thousands of connection (or find a network harnessing program)
backtrace the call and/or sniff the connection
where are you running the server?
at home? at work? at a hosting facility?
this will make a very big difference.
Can you design your app to connect to two sockets on the server and then load balance or make it active/passive (or active/active)?
You can use SO_KEEPALIVE TCP socket option.