My web app has been chugging along just great in Production for years with one App server and one Web server. Now we're moving to a multi-server environment with 2 App and 3 Web servers. I have enough time to make changes before the go-live.
As a Developer, what considerations should I take into account from coding, deployment, and architectural/ecosystem management perspectives?
Already on my list:
Remove tight-coupling between servers
Applicable files (i.e. downloadables) stored in IMAGE fields in SQL instead of files on app server
Deployment: Take out node out of the farm at a time
Have you given any thought to sticky sessions and cache management?
Related
I have an ASP.NET application running IBM Cloud, and I have a MongoDB instance created, and my application is deployed in my development-space, and bound to the MongoDB(alias). All working fine.
Now, I have also created a production-space, and want to deploy the application there, after having verified it in Dev.
But - do I really have to create another MongoDB - and pay for 2 instances, or can I somehow share one instance (with security seperating that dev cant access prod)?
Or what is best practice in this case?
Any advice much appreciated.
It is your call. The connection string to the mongodb will work from both dev and prod. I would recommend having two mongodb instances. A separate dev mongodb will allow development to work in isolation both functionally, performance and security.
I’m facing a deployment issue for my product. I have to deploy it on a couple of servers which are located on different countries. My product has 3 main components:
Application server: server and database (I'm using MongoDb)
User app: communicates with application server
Web server
Every application server can working independently. The requirements are:
The web server can access to all Databases and treat them as 1 single database.
The data of Application server 1 must be stored on its own database (not on Application server 2, or 3, or so on).
After googling around, 1 solution is deploying sharded clusters. Because I’ve never done this before, so is it a good idea? Will it meet the requirements? What points that I have to pay attention to when doing this? If it is not a good idea, please show me a good way to solve the problem.
Thank you very much.
I've deployed in Windows Azure a website made with Umbraco, using
Windows Azure Accelerator for Umbraco.
For development and test i used a test Hostname. Now it's time to switch to the official DNS hostname..
How can I change current hostname?
Actually i configured hostname at deployment time (the only way i know to do this) but i can't deploy again, since many files have been changed working on website on Azure.
EDIT
Let me explain: at the step prompt in the image (during web site deploying) I used as Domain Name "test.mywebsite.com", and configured real DNS.
Now the website is configured, so I'd like to make mywebsite.com point to that site;
But is'nt enough if i configure mywebsite DNS! Shall I deploy again? An will I lose any of the changes I made?
I'd like to make two comments on your question:
1) In order to host your Azure application under a custom host name, you will need to sign up with a DNS provider that supports C-NAME records (most do). I suggest someone like GoDaddy.com because by default C-NAME records can only resolve your "www.domainname.com" records and cannot do anything for queries where "www." is dropped from the URL. DNS providers like GoDaddy also have an option to redirect all traffic destined for "domainname.com" to a URL of your choice. This is a huge deal for Azure apps. Frankly speaking, it is somewhat disappointing that for all the PaaS and IaaS features of Azure, DNS was not included in the overall package.
2) I am a little worried when you say that you can no longer redeploy your app due to the changes made. Can you elaborate on that? Have you made changes to the application's code running on VM's in Azure without going through redeployment process? If so, this is a huge no-no. Your VM's running in Azure are not "permanent". Microsoft and your redeployment process can (and will) re-stage those VM's to the original package at any given time. Microsoft will re-image your VM's at least once a month during their monthly OS upgrades. But they can also do so when they need to move your VM to another rack, etc. Whatever changes that you make to your app must be either stored in source-control before deployment or in a permanent storage facility like SQL Azure, Azure Storage, etc.
HTH
Finally i think that the answers to my questions are:
-Shall I deploy again? Yes, i must deploy again
-Will I lose any of the changes I made? Many changes will be mantained since are stored into DB. But I have to do many activities to make new website work!
This answer confirms my theory:
In my case, I created and uploaded a site with a name, let's say
http://www.contoso.com and then paid a domain from a registrar let's say
http://www.example.com, when I mapped
http://MyAcceleratorsService.cloudapp.net/ to my new domain
( http://www.example.com ) and tried to open that domain I got the home page of
the Accelerator and not the uploaded site.
I had to upload the site again to Azure (using UploadUmbracoSite.cmd
from Accelerator application) and when uploading enter the same domain
name as the one I registered: http://www.example.com. Then, I was able to
browse my uploaded site as expected.
As for your question, will upload site again using
UploadUmbracoSite.cmd (is in the Setup folder) and will enter the new
domain name when requested.
Exactly what I was trying to avoid.. but the only solution, i suppose.
Well it was not easy to publish again, i got errors of many type (i suppose tied to some components that i've installed after deploy and that are not installed in new deployed website).. i'm going to solve them.
Edit
Completed my work:
- loads of different attempts, no-one worked
- CTP backup of DB
- deleted DB and website
- new full deploy of umbraco
- CTP restore of DB
finally:
-all work on content is OK
-all work on styles, pages, templates is lost
Changing hostname is hard; dont'use test hostname but definitive hostname from the beginning.
If anyone has suggest, i'll be pleased to test it, anyway
This is not really an answer to your question, but it might be a solution to your problem: Use a CNAME record to make the production DNS name point to your development name. E.g. www.productionname.com will the point to www.testname.com. I am not sure if everything will just work out of the box, but it seems to be worth a try.
This requires, that your hosting provider allows you to set up CNAME records.
http://en.wikipedia.org/wiki/CNAME_record
We use Windows Azure Cloud services to host our application. One of the great features of Windows Azure is the Production/Staging model. You can have the clients of your application routed to your production server, while you can test your new code running on a staging server. For example, you can configure Azure to point a production server to http://www.coolapp.com while designating a staging server for the same app to something like this: http://7f8e9d5ba73a4f7ea9ebd65a02ee195d.cloudapp.net.
Physically both of these servers are publicly facing. If you were to know the cryptic URL of a staging server you would be able to browse to the app just as easily as you would browse to www.coolapp.com. However, the presence of a GUID in the URL makes it virtually impossible for someone to guess it, thus making the staging server "private". This gives a nice mechanism to the developers of an application to deploy and test the new bits on a staging server before releasing them to public. Once they make sure that things look good, with a flip of a switch they swap the two servers, making staging server a production server and vice versa.
This model creates a small problem for us in relation to Facebook integration. To be able to integrate Facebook plugins you have to register your app with them. FB will then issue an AppId and an AppSecret keys. These keys are tied to the URL of your application. So in order for my app to work with FB plugins I need to obtain one set of keys that is tied to 7f8e9d5ba73a4f7ea9ebd65a02ee195d.cloudapp.net, and another set that is tied to www.coolapp.com.
When I read about Windows Azure, they really urge developers to treat staging vs. production servers as the same. The only difference between them should be the URL. In other words, Azure does not recommend basing your app logic on which server the code happens to be running on as Azure has no inherent knowledge of this. Staging vs. production is just a handy "abstraction" if you will. I guess you see the problem here. In our example above, I have to use one set of keys issued by FB versus another depending on which URL (production vs. staging) my app is running at. I assume I am not the first one running into this problem. What are the correct ways of handling this? One obvious way is to sniff the URL property of the Request object and branch my logic that way. However, intuition tells me this is a hack. Any other ideas?
Regards,
Archil
The mechanisms I know of are:
using "production" within a totally separate service account to "testing" - this leaves "staging" within the production service to be used as an area for "deployment candidates" and provides a separate clean testing domain with a non-changing URL for earlier "dev and test" work.
using different .cscfg files for staging and production - and being careful to update this .cscfg before you do any live switching.
sniffing the incoming URL - as you suggest
Personally, I use the first of these techniques - its easy and it helps prevent nasty accidents
As an aside, one of the techniques we've used for "removing" the Guid from staging is to CNAME the Guid with a really short TTL on the DNS - this allows us to quickly and automatically update the CNAME record for the staging server when we deploy.
We are having a massive system having around 15 servers hosting .Net WCF services, mvc application etc.
When we do a deployment (out of office hours) we have to uninstall and install everything on the live servers.
This takes lot of time and if something goes wrong we have to rollback everything.
can you please suggest something different to this?
like
Deply into a other environment (whenever you like) and switch the URL to point to new servers
[This comes with the overhead of cost of maintaining 2 copies of production (active and passive)]
any other ideas please.
Does services need to be uninstalled for all deployments ?
You can have a script that does this against all the servers in parallel:
Stop any windows services
Stop IIS
Make backup of replaced files
XCopy assemblies, resources, website files.
Perhaps run InstallUtil if deploying a service (as needed).
Start IIS and services.
Such a script will not take too long to execute. With 15 servers it will be well worth the effort writing it and make the deployment and rollback process completely automated.
It sounds like you need a load balancer to handle the trafic to your production servers. You would deploy all your new code to Server Farm B and test it using a test DNS entry. Once you are satisfied with the changes you would repoint your load balancer addresses from Server Farm A to Server Farm B it will then become live. The only down side to this is with database changes.