Any news on the status of this? I tried it with a service I'm developing to connect to my load-balanced mssql database and it continues to occasionally time out. I might try chrislukk's branch

@mitant Do you have any more information on when these timeouts happen?

Whats the status of this PR? The inability to set multisubnetfailover=true is a deal breaker. Any update would be greatly appreaciated. Cheers!

@takotuesday Would you mind taking this code and going on a test drive with it? @chrislukkk hasn't reported back.

Guys, the problem is not that you can't set "multisubnetfailover=true", it's that the functionality doesn't appear to exist in this driver package to behave in the way that multisubnetfailover=true is supposed to indicate.

@arthurschreiber The behavior that I observed in my testing was that it would behave the same as if the functionality wasn't implemented--that is if I pointed the connection at the "load balancing" host it would occasionally time out. If I point at the db instance behind the load balancing host, it will work flawlessly, but then it's not load balanced anymore.

Issue #396 has a similar issue but for some reason they can't connect at all. I personally was able to connect and perform operations for some amount of time, which later would timeout.

I'm on a project that we had to connect to a cluster DB. I'm using Sequelize as the connector wrapper, and it wasn't working until I took this code and manually put it in the node_modules/tedious folder. It's been in there for about a month, and we're just about out of UAT with no connection issues so far. So as far as my experience goes, this is working good. It solved the issue I was having immediately.

The project will go to Production in a few weeks so it'll get stress-tested then if that's what y'all are looking for.

@jblaketc Thank you so much for reporting back and letting me know that this is working for you!

@mitant Did you use a checkout of this Pull Request in your testing? As long as this PR is not merged, tedious does not support multiSubnetFailover. With this PR, the functionality should be implemented according to Microsofts specification.

I'm getting some good results. Earlier in the day pre-pull I was getting db timeouts on startup of my loopback project (which depends on tedious). I haven't observed any timeouts recently. As I do more dev work today I'll make a note if I run into any more issues

p.s. to anyone watching this thread, I used the following to load this pr
npm install git+https://github.com/tediousjs/tedious.git#pull/362/head

I have tested this and so far looks promising. After some initial issues with connection, i can reliably run my app tests and pass.

p.s. Thanks for the load link @mitant

Thanks everyone who tested this! ❤️

It looks like this is stable enough to be merged into master, but there's a consistent build failure with Node 0.10 on AppVeyor, and I'm not sure what is causing this. Once I figure that out, I'll get this merged. 👍

@arthurschreiber I tried running this on my local machine against Node 0.10 and am able to repro. I see the error below. In binary-insert-test.js, test.done() is being called from 'end' callback. Is it possible that this PR is somehow causing the callback to not be invoked? I tried adding callbacks for 'close' and 'error' but that didn't fix it. I'll look at this more later but sharing in case there is something here that may be obvious to you.

For some reason this part of the output is not there in on the failure link.

binary-insert-test:
FAILURES: Undone tests (or their setups/teardowns):

• insertBinary

To fix this, make sure all tests call test.done()

@tvrprasad Thanks for checking this out! I've not been able to reproduce this so far, but the output you pasted at least gives me some sort of direction! 😄

I'll try to take a deeper look into this after the weekend - hopefully we can find out what's wrong here so this can be merged and released soon!

@arthurschreiber Just for FYI, I was able to repro with Node version v0.10.46, running on Windows version 10.0.10586.

@takotuesday I just pushed another change that would need review from @tvrprasad, then we should be good to go and release this as 1.15.0.

@tvrprasad Would you mind taking another look? I added multiSubnetFailover support when connecting via an instance name instead of specifying a specific port. It only supports UDPv4 now, do you think we need support for UDPv6 as well? The change is in 2a7462d.

@arthurschreiber I think we should support UDPv6 to stay consistent with the non-instance name based code path. Also, I added a couple of other review comments.

Thanks for the updates!

Sent a PR to address remaining issues with MSF. #502

@arthurschreiber The sender tests are failing in 0.10 and 0.12. I'll take a look.

This is awwwwwwwwwwweessoommmmmeee, thank you @arthurschreiber!

Releasing this as 1.15.0 now.

Also, thank you to everyone who helped getting this over the finish line 🏁 !

This is great! Thanks :-)

Hi @arthurschreiber,
I'm working on a project and I need Sequelize to be able to use tedious with multiSubnetFailover to true. However, I can't find a way to do this. Is there a "clean" way to change tedious's behavior to have multiSubnetFailover property enabled by default ??
Thanks a bunch!

@amihanov, you should be able to just pass the MultiSubnetFailover setting as a dialect option when initializing Sequelize.

@renaudholcombe, Yes!! thanks. it worked great. Here's the code (in case some can use it):

var Sequelize = require ('sequelize');

var config = {
  adapter: 'mssql',
  host: 'myHost',
  user: 'myUser',
  password: 'myPassword',
  port: 1433,
  database: 'myDatabase',
  dialectOptions: {
    multiSubnetFailover: true
  },  
  pool: {
    max: 5,
    min: 0,
    idle: 10000
  },
  maxConcurrentQueries: 100,
  logging: false
};

var sequelize = new Sequelize(config.database, config.user, config.password, {
  host: config.host,
  port: config.port,
  dialect: config.adapter,
  dialectOptions: config.dialectOptions,
  pool: config.pool,
  maxConcurrentQueries: config.maxConcurrentQueries,
  logging: config.logging
});

sequelize
  .authenticate()
  .then(() => {
    console.log('Connection has been established successfully.');
  })
  .catch(err => {
    console.error('Unable to connect to the database:', err);
  });