NGINX Ingress controller not updating affinity cookie - session

Question

The nginx ingress controller in out Kubernetes cluster should route the traffic according to a optional session cookie (the SHA1 hash of the ip and port). However, when I send a random value as cookie, no real cookie is set instead. This also happens when the target server is not alive any more.
* Trying 148.251.XXX.XXX...
* TCP_NODELAY set
* Connected to **********.com (148.251.XXX.XXX) port 444 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Client hello (1):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384
* ALPN, server accepted to use h2
* Server certificate:
* subject: CN=*.********.com
* start date: Oct 17 06:25:15 2018 GMT
* expire date: Jan 15 06:25:15 2019 GMT
* subjectAltName: host "********" matched cert's "*.********.com"
* issuer: C=US; O=Let's Encrypt; CN=Let's Encrypt Authority X3
* SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0x55d70debd8e0)
> GET /management/health HTTP/2
> Host: ***********.com:444
> User-Agent: curl/7.58.0
> Accept: */*
> Cookie: cv-sid=aa; Domain=**********.com; Path=/; HttpOnly
>
* Connection state changed (MAX_CONCURRENT_STREAMS updated)!
< HTTP/2 200
< server: nginx/1.15.2
< date: Mon, 29 Oct 2018 12:18:34 GMT
< content-type: application/vnd.spring-boot.actuator.v1+json;charset=UTF-8
< x-application-context: ********:kubernetes:8443
< x-content-type-options: nosniff
< x-xss-protection: 1; mode=block
< cache-control: no-cache, no-store, max-age=0, must-revalidate
< pragma: no-cache
< expires: 0
< strict-transport-security: max-age=15724800; includeSubDomains
I found a PDF of the authors that explains the flow that I expect.
Update: The output of kubectl describe ingress ... is:
Name: ingress
Namespace: default
Address:
Default backend: default-http-backend:80 (<none>)
TLS:
tls-certificate-tmp terminates
Rules:
Host Path Backends
---- ---- --------
***.com
/ ***-service:80 (<none>)
Annotations:
nginx.ingress.kubernetes.io/rewrite-target: /
nginx.ingress.kubernetes.io/session-cookie-name: sid
nginx.ingress.kubernetes.io/ssl-redirect: true
nginx.ingress.kubernetes.io/proxy-body-size: 50M
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/affinity: cookie
nginx.ingress.kubernetes.io/session-cookie-hash: sha1
kubectl.kubernetes.io/last-applied-configuration: ...
Events: <none>