I am hosting a service on Windows Azure and using an external DNS (Gandi) to manage zone files. What I would like is to redirect all the incoming Azure traffic to another web page, while I am updating the service (like we'll be back soon).
I know that I can do this by updating the zone file, but it takes time to propagate, then time to put back into normal. So 1 hour update finally takes 6-8 hours.
This is not good. Is there any other way to redirect traffic with IMMEDIATE effect and not wait DNS to propagate? Adding redirection inside the code is not really an option, because Azure service packages take an eternity to upload.
Thanks
Not sure what your full requirement here is, but could VIP swap do the trick for you?
You would deploy the alternate 'well be back' site to the staging slot and when you wish to update the service you'll use VIP swap to make that production whilst you update your service, which is now on staging with the latest build.
When that's ready you can VIP swap back and the new site is now in production?
Edited to add:
I take your point regarding wanting to leave the staging slot for rollbacks, makes perfect sense.
Another option could be to use the Traffic Manager -
Have your main application in one cloud service and your temporary landing page in another.
Configure a traffic manager failover policy with both services (main one first, alternative second).
when you want to go to 'maintenance mode' disable traffic to the main service and all traffic will get routed to the 'maintenance mode' one although there is some lag in propagating it measured in minutes rather than hours when I played with it a little bit just now - there's a DNS time-to-live setting available to you which defaults to 5 minutes.
When you're ready to come-back online re-enable the main site (and you can chose to remove the 'maintenance mode' deployment when all is working
There's a feature in ASP.NET to quickly stop serving content. If you put a file called app_offline.htm in the root of the site, it will serve that instead of regular content. There are details in this blog post.
Using it in Azure may be difficult. I would suggest using VIP Swap, but I see you don't want to do that. You could remote into each VM and manually add the file, though that could be painful. It may be possible to script it, but I don't know an easy way to do so.
Related
I have a static web app to which I have mapped the domains [domain].se and www.[domain].se. The domain is managed in Azure.
The problem I'm facing is redirecting all calls to [domain].se to www.[domain].se
Since I couldn't come up with any solution to redirecting http traffic from [domain].se to www.[domain].se using a static web app (other than setting up an additional standard web app on [domain].se that manages redirects), I enabled the "Enterprise-grade edge" feature (which by the way is a very silly name) to be able to use FrontDoor.
When attempting to add the domain to the frontdoor resource, there is an error message telling me that it's already mapped to something (which is correct - the site that I want frontdoor to manage).
When trying to remap [domain].se (and www.[domain].se) to the front door endpoint (select Azure resource in the DNS zone manager), the frontdoor resource is not available.
The issue could probably be resolved by simply removing the current records from the name server and then add a cname record to point it to the frontdoor endpoint.
Two reasons not to do that:
1: It would cause downtime.
2: It feels like a hack. Stuff genereally work better when they are used the way they were expected to when developed. I want the platform to recognize what things are connected in order to avoid future issues.
I'm in the use case where I had nothing on this domain, nothing was started on either side, I just bought the domain on the wrong service.
I imagine it's possible to transfer ownership to AWS, so that I may start managing the DNS from there rather than from dreamhost.
I probably could have purchased the domain from route 53 in the first place but this is now done and I don't want for the year under dreamhost to time out to start using it. nor do I want to use dreamhost to manage this url since dreamhost charges quite a lot more.
I've found the amazon guide that's my exact situation, but as per ususal with these guides they're super afraid of providing a concrete example and get into super abstracts with reused terminology for different meaning resulting in an unusable jumble of uncertainties : https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/migrate-dns-domain-inactive.html
So I've gotten to :
Step 3: Create records (inactive domains)
I've just manually edited the values that were created by default by route 53 when I created that hosted zone to the ones I found in the dreamhost DNS configuration :
but I doubt that's what I have to do to transfer the domain especially since the step after that basically sais to change it back to what it was.
So what is it exactly I'm supposed to do in order to transfer the domain to amazon (route 53)?
Domain registration and DNS resolution are related, but separate entities. It seems like you decided you want route53 to serve your DNS entries. Given that, you have two choices.
Choice 1: Keep domain registered with dreamhost
If you do this, you need to instruct dreamhost to look up DNS entries for your domain at route53. This can be accomplished by setting the NS servers on dreamhost to point to route53. There are detailed instructions for this at AWS here. What you have in your step3 is backwards. Step 3 is just saying if you want HOST.yourdomain.com, to add a entry 'HOST' into the hosted zone. You should not touch the NS or SOA entries on the route53 hosted zone away from their original settings. You can simply delete the zone and start over again.
Background: Dreamhost will populate the NS entries by default and they will be the ones queried how to resolve HOST.yourdomain.com. However, if you don't provide dreamhost any information that they should refer the requests to route53, it has no way of knowing that. You need to tell dreamhost that the NS entries (Nameserver) should point to route53's servers. That way, the user trying to resolve HOST.yourdomain.com will be pointed to route53. When it asks route53 what the IP is, all will be well if you setup your hosted zone to resolve that entry. This is what you are going to do on step 4 from the AWS documentation.
Choice 2: Transfer your domain registration to route53
This is a little more up front work, but may be easier in the long run. You are permitted to transfer the domain to another domain registrar. You'll have to follow instructions at both the giving side (dreamhost) and the gaining side (route53).
NOTE: ICANN does enforce a 60 day lock on moves. If you just registered your domain, you will need to wait 60 days before the transfer process can begin. Also, do not worry about 'double paying' for the year. You are required to purchase at least one more year of domain registration, but it will be appended to the end date of your expiration (it won't start it over). Once you move to route53, especially if you already are using route53 for the hosted zone, you will have one less place to pay and administer.
Additional NOTE: Because of the 60 day lock, if it has been less than 60 days since you created the domain, choice #1 is the only choice during that period if you want to serve DNS records from route53.
me again..
I had done all the sensu-uchiwa-graphite set up. And i get a new request,:(. Rather than go to change the threshold in check.json file on sensu server..any plugin at the UCHIWA that this adjustment will be shown in Uchiwa dashboard? I asked because in case that my application teams wanna change it by themselves without accessing to server.
I think sensu-admin in enterprise is available but we need to pay big money per year ;(...
Thanks in advance to help.
Sumana W.
This is fairly doable if you use a configuration management system like Chef/Ansible/Puppet - especially if you run standalone checks on the sensu-client.
This allows the clients to define their own thresholds, rather than changing the sensu servers themselves.
See https://sensuapp.org/docs/latest/reference/checks.html#standalone-checks
In this case, the definitions for the checks are sitting on the client servers and they have the choice of their thresholds or configurations. The client itself manages how often to run the check and sends the output back to the server, rather than the server requesting the checks. This helps quite a bit as far as scaling or multitenancy.
The other way to accomplish this, if you are tied to serverside checks, would be to use client attributes (https://sensuapp.org/docs/0.25/reference/checks.html#check-token-substitution)
For example, you can have a cpu check that says something like check-cpu.sh -w :::cpu_warn::: -c :::cpu_critical::: and these come from a cpu_warn and cpu_critical value from the client.json on the client server.
Source: We use sensu extensively in an enterprise environment across thousands of hosts and have been working through these same issues.
I am often working with websites to which I have no code access but for which I need to test javascripts, ajax calls and other resources in locally modified versions.
As an example I needed to test a new creative code originally coming from a DoubleClick server. Instead of working directly on DoubleClick and loose a lot of time waiting for my changes to take effect I needed to manipulate a local copy of that javascript resource.
So I changed my /etc/hosts to point the DoubleClick server to localhost where I run a local web server. This way I was able to test a local script instead of the original.
Of course this redirected all resources and not only the one i was interested in what often results in either weird behaviour as resources become unavailable or a lot of effort on my part to make them available.
Is there a way to replace a specific URL by redirecting it to a local file/URL and let all the others from the same origin be untampered?
We have an internal web system that handles the majority of our companies business. Hundreds of users use it throughout the day, it's very high priority and must always be running. We're looking at moving to ASP.NET MVC 2; at the moment we use web forms. The beauty of using web forms is we can instantaneously release a single web page as opposed to deploying the entire application.
I'm interested to know how others are deploying their applications whilst still making them accessible to the user. Using the deployment tool in Visual Studio would supposedly cause a halt. I'm looking for a method that's super quick.
If you had high priority bug fixes for example, would it be wise to perhaps mix web forms with MVC and instead replace the view with a code-behind web form until you make the next proper release which isn't a web form?
I've also seen other solutions on the same server of having the same web application run side-by-side and either change the root directory in IIS or change the web.config to point to a different folder, but the problem with this is that you have to do an entire build and deploy even if it were for a simple bug fix.
EDIT: To elaborate, how do you deploy the application without causing any disruption to users.
How is everyone else doing it?
I guess you can run the MVC application uncompiled also? and just replace .cs/views and such on the run.
A websetup uninstall/install is very quick, but it kills the application pool.. which might cause problem. Depending on how your site is built.
The smoothest way is to run it on two servers and store the sessions in sql server or shared state. Then you can just bring S1 down and patch it => bring s1 back up again and bring S2 down => patch S2 and then bring it up again. Al thought this might not work if you make any major changes to the session parts of the code.
Have multiple instances of your website running on multiple servers. The best way to do it is to have a production environment, a test environment, and a developement environment. You can create test cases and run the load every time you have a new build, if can get through all the tests, move the version into production ;).
You could have two physical servers each running IIS and hosting a copy of the site. OR you could run two copies of the site under different IIS endpoints on the SAME server.
Either way you cut it you are going to need at least two copies of the site in production.
I call this an A<->B switch method.
Firstly, have each production site on a different IP address. In your company's DNS, add an entry set to one of the IPs and give it a really short TTL. Then you can update site B and also pre-test/warm-up the site by hitting the IP address. When it's ready to go, get your DNS switched to the new site B. Once your TTL has expired you can take down site A and update it.
Using a shared session state will help to minimise the transition of users between sites.