Dockerized spring cloud gateway can reach dockerized keycloak via his public dns - docker

Question

In a microservices architecture, I have three containers, front(angular), gateway(spring cloud gateway) and security provider(keycloak) among others
For security configurations in the gateway
If I set
spring:
security:
oauth2:
client:
provider:
keycloak:
issuer-uri: http://keycloak-container:8080
I can start gateway container and reach the security container
But
spring:
security:
oauth2:
client:
provider:
keycloak:
issuer-uri: https://public-dns-of-keycloak-container.mydomain.com
Throws me this error
... 61 common frames omitted
Caused by: org.springframework.web.client.ResourceAccessException: I/O error on GET request for "https://public-dns-of-keycloak-container.mydomain.com/auth/realms/boromoi_app/.well-known/openid-configuration":
Connection timed out (Connection timed out); nested exception is java.net.ConnectException: Connection timed out (Connection timed out)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:751) ~[spring-web-5.2.1.RELEASE.jar!/:5.2.1.RELEASE]
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:654) ~[spring-web-5.2.1.RELEASE.jar!/:5.2.1.RELEASE]
at org.springframework.security.oauth2.jwt.JwtDecoderProviderConfigurationUtils.getConfiguration(JwtDecoderProviderConfigurationUtils.java:71)
~[spring-security-oauth2-jose-5.2.1.RELEASE.jar!/:5.2.1.RELEASE]
... 69 common frames omitted
Caused by: java.net.ConnectException: Connection timed out (Connection timed out)
https://public-dns-of-keycloak-container.mydomain.com is the URL used by front to reach security container