IIS -> Lock .NET Core application DLL file

[radenkozec]

When I try to overwrite .NET Core application DLL file using FTP on production IIS server file is locked and it cannot be overwritten.

To deploy new version I need to stop application in IIS to release lock, then overwrite.
It is not possible to deploy without stopping application.

[Tratcher]

See app_offline.htm: https://docs.asp.net/en/latest/hosting/aspnet-core-module.html#asp-net-core-module-app-offline-htm

[guardrex]

If you end up desiring a PowerShell way of doing it, you can use the IIS Admin cmdlets: https://technet.microsoft.com/en-us/library/ee790599.aspx

Stop-WebAppPool -Name $appPoolName

... deploy ...

Start-WebAppPool -Name $appPoolName

[radenkozec]

Thanks for explanation @Tratcher .
I am not sure if this is on your plans but this worked for previous ASP.NET MVC I think?
Do you plan to implement this feature or not?

@guardrex I cannot do it because it is shared hosting enviroment and don't have permission to stop AppPool

[chuchuva]

Can you make it to 'just work' with msdeploy.exe and Azure? If I understand correctly the web site needs to be restarted to prevent file locking. -enableRule:AppOffline works but the whole website is offline for few minutes which is not a great user experience especially given that we deploy few times per day.

See also http://stackoverflow.com/q/40276582/14131

[Tratcher]

@chuchuva maybe, but all magic comes with a cost. Previous versions of ASP.NET did some complicated shadow copying to work around the file locking problems.

[HarelM]

Magic or not, It worked well. I kinda miss it now after the migration to ASP.NET core...

[JaCraig]

Agreed with @HarelM. We've run into issues with this from our automated deployments to just end user experience. We've gone from deploying about 10 times a day with the old MVC to maybe a daily deployment at night and accepting that the people using the Core app are going to be annoyed when we take it offline. While not a show stopper, it's added friction towards Core adoption.

[cyriltovena]

👍

Not supporting overlapped recycling is a regression.

[deadlydog]

Are there plans to revisit this feature and put it on the road map? It's very inconvenient/unfriendly to require everybody deploying a .Net Core website to manually implement a staging-slot strategy if they want to support zero downtime deployments.

Having this feature would make the transition to .Net Core websites much smoother for many people, and would allow for faster adoption of .Net Core websites.

[ajeckmans]

We would like to know as well. Putting a app_offline.htm inside the applications directory does not work.

[DaleMckeown]

I've only just realised this 'feature' after moving a number of sites over to AspNetCore. I can't believe it's deemed to be acceptable to take your sites offline for a few minutes every time you want to publish!

This is bad enough for me as a leader of a small team - are those practicing continuous integration on a large scale shunning AspNetCore? There is no way they would be able to have their site going offline for minutes every hour to republish!

[davidfowl]

Are you deploying use FTP or xcopying? Or are you using webdeploy?

[DaleMckeown]

I'm publishing via webdeploy to IIS.