Up to now I have never worked with bonjour. I think it is an interesting approach for using it to discover hosts which run rest services (e.g. by defining a predefined URL for devices providing a specific service).
I read that I can ping the host with Bonjour via the bonjour-name but I have not found an approach how to call a REST service with bounjour (where I usually also need the port). Is this possible or do you know some references? I am thinking on something like this: xservice.Alice.local/rest?abc=......
Thank you
Related
I know that 'servicePort' is used by marathon-lb to identify an app. Is there any other user of this setting besides marathon-lb?
If the answer is no, why is it mandatory (omitting it well generate one for me)? I have many marathon apps which are not managed by marathon-lb, and they all take up service ports by default.
From the documentation: ""servicePort" is a helper port intended for doing service discovery using a well-known port per service. The assigned servicePort value is not used/interpreted by Marathon itself but supposed to be used by the load balancer infrastructure."
So service ports seem to have no other use other than for marathon-lb.
When you don't specify a servicePort, its as if you put in "servicePort": 0.
See closed issue here.
Here's a discussion about the re-architected networking API.
If you look at the Jira ticket, you will see that the new API model lets you define services without servicePorts at all.
We have created self-hosted services using OWIN. They are working fine inside the server and we can request and retrieve information using the http://localhost. We use a different port for each service so that we can go and get certain information from http://localhost:8001, other from http://localhost:8015 and so on.
Now, we need to expose the results of one of those self-hosted services to access to it through internet. We'd like to provide a custom address such http://ourpublicinfo.mydomain.com:8001 or using the server ip such http://209.111.145.73:8001.
Is that possible?
How can we implement it?
Our server OS is Windows Server 2012 R2
OWIN Self-Hosted apps can run on a Windows Service, as a Console process and, with if desired, as part of a more robust Host like IIS.
Since you mention your app is running as a service you're probably missing all the GUI goodies IIS provides. In reality however, IIS works on top of http.sys, just as HttpListener does (which is probably what you're using to self-host your app) 1. You just need to do some manual set up yourself:
First of all, you need to make a URL reservation in order to publish on a nonstandard port.
Why would you do that? Quite simply because you're not running under localhost alone anymore on your very own local machine, where you probably are an admin and/or have special privileges/powers.
Since this is a server, and the user used for running the Service might not be an admin (most probably), then you need to give permission to that user to use that URL... and here is where URL reservations come into scene.
You pretty much have to options:
open up the URL to be used by any user:
netsh http add urlacl url=http://209.111.145.73:8001/ user="everyone" listen=yes
or open up the URL to be used by the user(s) running the service, e.g.: NETWORK SERVICE:
netsh http add urlacl url=http://209.111.145.73:8001/ user="NETWORK SERVICE" listen=yes
There is a way to make the reservation for several users too, using sddl, user groups, etc... but I'll not get into it (you can look that up).
Second of all, you need to open up a hall through your firewall (if you don't have one on this day and age, I pity you!)
There are plenty of tutorials on this. You can use a GUI, netsh.exe and what not.
Pretty much all you need to do is make sure you allow incoming connections through that port and that should do the trick.
To make sure the hall is open through and through you can use a tool like http://www.yougetsignal.com/tools/open-ports/ and insert 209.111.145.73 in the Remote Address and 8001 in the Port Number.
If for some reason it shows that the port is closed, even after creating an incoming rule in your firewall for it, then you probably have one or more firewalls in between your server and the outside world.
With those to elements in place you should be able to access your Self-Hosted Service from the outside.
As for accessing your service through an address like http://ourpublicinfo.mydomain.com:8001, you'll need to create a DNS entry somewhere, most likely on your Domain Registrar for mydomain.com, where you could create an A Record for your ourpublicinfo subdomain pointing to 209.111.145.73.
From this point on, you should be able to access your service through direct IP and Port or through the afore mentioned URL.
Best of luck!
Note:
If your service will be access from other domains, you might need to make sure you have CORS (Cross Origen Resourece Sharing) well defined and working on your service too ;)
I have a standalone, embedded Eureka server powered by Spring Boot 1.2.0.RELEASE and Spring Cloud 1.0.0.RC1. I see services properly registering themselves in the dashboard, which is great. The status links are using the host name of the box they are running on. Unfortunately, we are using virtual machines and they don't register themselves in DNS, which means that the links are unresolvable. I started looking through the code but was unable to find a way to force the links to use the host's ip address instead. Having a broken dashboard is not the end of the world but I am afraid that once we start using Ribbon or Feign to contact services, those URLs will also use the host name and be unresolvable. Maybe what I am really asking is there a way to force the clients to register with an ip address instead of a host name? Any help is appreciated.
set eureka.instance.preferIpAddress=true as documented here
I want to use some sort of nmap-like functionality to autodiscover a ASP.NET web server (running on port 443) somewhere on the network. This way users don't have to find and enter the IP manually. Is there a good/clean way to do this?
Thanks to #ceejaoz's comment above, I was able to do this pretty easily in Bonjour.
I used Mono.Zeroconf, a .NET/Mono Bonjour library, to advertise the service, and the default iOS NSNetService stuff to resolve it on the iPhone. (There's plenty of tutorials on how to do this around the nets).
I made a Windows Service in Visual Studio to actually run the code that advertises the ip and port, since a web service isn't really a good place for that.
One big caveat (as of December 2010): the Bonjour DLLs that come with Mono.Zeroconf are totally broken (no errors, they just don't do anything). Steal the ones from Pidgin instead.
It seems that both service and server refer to some web based application. But is there any precise definition of the two terms?
A server offers one or more services. Server is also a more technical term, whereas service is more a term off the problem domain.
You also need to distinguish between:
Server as hardware (see post from Dan D)
Server as software (eg. Apache HTTP server)
You can find more elaborate definiton on Wikipedia:
Service
Server
This is regardless of client-server or P2P models.
A server provides services to one or more clients, and a server(hardware) is a computer. A server(hardware) can be anything from a home computer to a big server-rack with a lot of processor power.
From the view of a computer, a server(software) is just a set of services which is available to clients on the network.
Some well known services are web-server, mail-server. ftp-server. notice they are called xxx-server because such programs consist of a client and server part. The postfix is mainly to distinguish whether we are talking about the client or the server.
So at what moment do we call something a server? We do it when a computer shares some service/content on the network, which is accessible by clients. In other words, when we make a server as defined for software.
Regarding the P2P model: every one is both a client and a server, hence called servent. The above apply to the server part of a P2P network, just remember that it also can be a client.
Futher reading:
Client-Server model
P2P
a server is a piece of hardware or on a virtual machine
a service is a process that provides services normally over the network and runs on a server
but a server can also refer to a web server which is actual a service but it's sort of like one as it hosts services
i think those are reasonable working definitions
I think a simpler way to define both besides the definition of the server being a piece of hardware, a server in the software sense is a service that serves data. In other words you interact with a server with a request and you should get a response back. It "serves" data.
A service does not need interaction and is pretty much just a random process that keeps running doing the same thing, but a server is a service because it is basically a process that keep waiting for a request to come in so that it can return a response.
"A service is a component that performs operations in the background without a user interface."
~ Android Developers
Services don't just run on servers
Shell services
Services can run from the shell. Unix refers to services as Daemons (pronounced "demons"), and Windows refers to them as services.
Client-side services
Services can run client-side. Mozilla (and other browsers) support Web Workers which run in a background thread. Client-side frameworks, like Angular, support services as well.