Node.JS Server Cuts Off Frequently? - stream

I have a Node JS Server where I am using Socket.IO to stream content to the browser. It works great for about 45 minutes or so of streaming, then it will usually cut out. There are no "errors" reported in the terminal and the Node server acts like it is in, however the page I am serving clearly stops working.
What are my options for trying to get to the bottom of this? Could this be a configuration issue with Node/Socket.IO? is there any basic error logging you would recommend I setup?

Hard to say without seeing your code, but Socket.IO for NodeJS requires a heartbeat to maintain connection. It could be a bug in the client code for sending the heartbeat.

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SignalR Issue when Load Balanced on Netscalers

We are attempting to deploy a SignalR site on a Citrix NetScaler, as opposed to the current deployment on a single server. There are three servers in the farm. If you navigate to any single server, SignalR comes up fine. If you go to the NetScaler address, you get this:
WebSocket connection to
'wss://mysite.com/myapp/signalr/connect?transport=webSockets&clientProtocol=1.5&connectionToken=(token_displayed_here)'
failed: Error during WebSocket handshake: net::ERR_CONNECTION_RESET
After this error, there is about a 10-15 second delay, then it starts working. If I attempt to disable websockets as I have read that Netscalers still have issues with them, the error goes away but the delay remains. I believe the delay is caused by it trying to connect with ServerSentEvents and failing that as well. It appears that only long polling may be working over the NetScaler.
We have checked the NetScaler websocket settings, made sure the servers have the correct machine keys, had a backplane set up (tried Redis and an Oracle Nuget package as that's our typical DB), checked the OWIN versions and web.config settings, all of the stuff that Google told me to do that I could find but still get this error and delay. One thing that I did find is that Netscalers have issues with wss, but haven't been able to find anything about how to account for this. Most of the information found was for people using other load balancing technology.
Is using SignalR (or more specifically, WebSockets or ServerSentEvents) with a NetScaler even doable, and if so what could be causing this problem?

WSO2 ESB connections issue

Am working with wso2esb4.9.0 and having around 160 services which are http and are processed frequently, Initially when the server is started every thing is fine all service request response is up to the mark,
After 10-12 days the ESB server gets hanged does not process any request and no exception are seen in the log file even,They are some request which may be piled up in the server and not allowing new connection to process.
when i do restart of the server all the connections get releases and works for other 10-12 days again.
But doing a restart of the server may not be a good idea to do , where can i find these connections and close them if possible and am i missing any config changes of wso2 esb.
Am trying to find some different connection number using JMX and also what to know if any one face this issue and found the possible solution.

Twilio IP Messaging token issue

I'm setting up an iOS app to use the IP Messaging and video calling apis. I'm able to connect, create channels and setup a video call if I manually create hard-coded tokens for the app. However, if I want to use the PHP server (as described here https://www.twilio.com/docs/api/ip-messaging/guides/quickstart-ios) then I always get an error and it can't connect anymore.
I'm attaching a screenshot of what I see when I hit the http://localhost:8080 address which seems to produce a 500 Internal error on this URL: https://cds.twilio.com/v2/Streams
Thanks so much!
After much time spent on this I decided to try the node backend instead - under other server-side languages of the PHP and I have it running in 2 minutes! I used the exact same credentials as the ones that I was using on the PHP config file so either my PHP environment has something strange or the PHP backend needs some fixing. In any case, I'm able to move forward using the node backend, so if you run into the same issue just try node instead of PHP. woohoo!

SOAP server couldn't work correctly behind some proxy/firewall

I have a SOAP server/client application written in Delphi XE working fine for some time until a user who runs it on Windows 7 x64 behind a corporate proxy/firewall. The application sends and receives TSOAPAttachment object in the request.
The Problem:
Once the first request from this user is received and processed, the server could not process any request (from any user) successfully coming after this.
The server still response to the request, but the SOAPAttachment of the request
seems corrupted after the first one from this user, that's why it couldn't process the request successfully.
After putting may debug logs to the server, I noticed the TSOAPAttachment.SourceStream in the request's parameter become inaccessible (or empty), and TSOAPAttachment.CacheFile also empty. Therefore whenever trying to use the SourceStream, it will return Access Violation error.
Further investigation found that the BorlandSoapAttachment(n) file generated in the temp folder by the first request still exist and locked (which should be deleted when a request is completed normally), and BorlandSoapAttachment(n+1) files of the following request are piling up.
The SOAP server will work again after restarting IIS or recycle the application pool.
It is quite certain that it is caused by the proxy or the user’s networks because when the same machine runs outside this networks, it will work fine.
To add more mystery to the problem, running the application on WinXP behind the same proxy have no problem AT ALL!
Any help or recommendation is very appreciated as we have stuck in this situation for some time.
Big thanks in advance.
If you are really sure that you debugged all your server logic that handles the attachments to attempt do discover any piece of code that could failed specifically on Windows 7, I would suggest:
1) Use some network sniffer Wireshark is good for this task, make two subsequent requests with the same data/parameters values, and compare the HTTP contents. This analyze should be done both in the client (to see if the data is always leaving the client machine with the same content) and also in the server, to analyze the incoming data;
2) I faced a similar situation in the past, and my attempts to really understand the problem was not well succeed. I did workaround the problem sending files as Base64 encoded strings parameters, and not using the SOAP attachments. The side affect of using Base64 its an increase of ~30% in the data size to be sent, and this could be significant if you are transferring large files.
Remember that SOAP attachments create temp files in the server, and Windows 7 has different file access rules than Windows XP. I don't know if this could explain the first call being processed ant the others not, but maybe there are something related with file access.
Maybe it is UAC (User Access Control) problem under Win 7. Try running the client in win 7 "As Administrator" and see if it is working properly.

How to check the cause for a HTTP request latency/waiting time?

I issue a simple GET request to my server, and it's coming back after ~1.2 seconds on average (using firebug NET tab, the "waiting for reqponse" part- not even the whole reponse time)
My ping to the server is 0.250
Using Passenger with rails 2.3.3, in the rails log the request is taking ~0.023
My server is on GoDaddy, so I checked their homepage with firebug also- the "waiting for reqponse" time for their page is ~0.320
Worst case should be around 0.4... so where did I lose the other 0.8 seconds?
What else can I check?
Edit:
Seems like it's unrelated to rails-
An image request (that only apache responds to, doest hit the rails at all) takes ~1.2 seconds also
GoDaddy may have a reverse-proxy between you and your HTTP server.
They may be doing something like sending you the response headers right away, then possibly serving you the contents of the response from cache.
So, from the standpoint of your HTTP server, the response is transmitted. Then it goes to GoDaddy's reverse-proxy, then finally to your web browser.
Try setting PassengerPoolIdleTime to 0 in your Servers or VHosts configuration.
Maybe your server is shutting down the application instances to fast and spawns a new instance with every request which usualy takes quite long.
Take a look at the documentation for more information on this setting:
http://modrails.com/documentation/Users%20guide%20Apache.html#PassengerPoolIdleTime
Where your files are hosted from for GoDaddy is not the same as where their homepage is hosted from.
Have you checked other pages you have hosted on the same server? Possibly due to database connections or "slow" connections like that can cause the page to take awhile before it's sent back to the client.
Doesn't sound like it is your problem, but the ISP's.
Can you do a wget to an internal ip/port to your rails app directly (or apache) from the same server?
That will tell you if the probaby is in the app stack or further upstream.
If you can, you can use apache tool, called ab "apache benchmark" to help.
The key is having a ssh access to your computer.

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