If a microservice is down, how to route to another online instance?

[sanazsasan]

hello Ocelot community! can you help me?
We use the ocelot api gateway to route and manage microservices. We want to deploy two instances of a microservice and we want to do routing by ocelot when one instance is down or crashed, ocelot routes to the other instance. How can we implement?
my email: mhedayati1357@gmail.com

[raman-m]

Hi @sanazsasan!
Welcome to Ocelot world! 🐯

when one instance is down or crashed, ocelot routes to the other instance.

Could you clarify your request, please? I believe you're referring to load balancing, correct?
In a load balancer scenario, if one service is down, Ocelot does not search for the next available service in the configuration, unfortunately. Many of our open issues related to Load Balancer report the same problem; you can see all issues here. For instance, issue #1041 describes the exact problem with a down service.
So, this new feature will be developed when work begins on issue #1041.

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How can we implement?

Until the issue in the Ocelot kernel is resolved, there is only one development alternative:

• Custom Load Balancers

Is my understanding of your user scenario correct?

[sanazsasan]

@raman-m
we have an infrastructure to keep stabling payment services base F5. When we decided using Oclot API Gateway, We must deploy the same as F5. For example, We have an ocelot api gateway server for routing and load balancing and We have 4 microservices on 8 servers that are identical two to one, only their port and IP are different. If one of those peers goes out of service for some reason, the request is sent to that peer through the ocelot api gateway.

[raman-m]

Sanaz,
It is important to recognize that Ocelot is not liable for downstream disasters. Should a service fail, Ocelot will log the event and issue an Error Status Code, likely a 502 or 503, as detailed in the Server Error Responses section.
And as I said, wanted functionality for Ocelot's Load Balancers is not implemented yet.

Are you developer or manager?
What country are you from?
What's your LinkedIn?
If you do not want to post information publicly, please send responses to "dotnet044 [ at ] gmail [ dot ] com", this is my work email.

[sanazsasan]

@raman-m Thanks for your response I send private information about me to dotnet044 bla gmail bla com.
I solved this problem by dynamic routing in API Gateway.

[raman-m]

@raman-m Thanks for your response I send private information about me to dotnet044 bla gmail bla com.
I solved this problem by dynamic routing in API Gateway.

Congratulations! 🎉
Do you use Consul or other service discovery tool?
Definitely, using Consul should help because Consul has features such as Health Check and it should build the dynamic list of online services filtering offline ones.

[sanazsasan]

Hi @raman-m
Yes, I implemented dynamic routing by service discovery tools.