Login session not saved/redirected on log in

I’m running the image grafana/grafana:6.2.2 across an AWS cluster. It’s running with a shared postgres database for users/dashboards. I’m also using redis as a cache. I’m basically following the HA setup here https://grafana.com/docs/tutorials/ha_setup/.

When I log into the instance, it keeps redirecting me to the read-only view of the charts - not saving my session. I basically cannot log in. I’m sure I’m using the correct credentials, since when I try another username/password combination it rejects it. I’m wondering if anyone’s had this experience before. I feel like I’m missing something small here.

My config variables are:
GF_AUTH_ANONYMOUS_ENABLED = true
GF_DATABASE_HOST = <postgres_endpoint>
GF_DATABASE_MAX_IDLE_CONN = 10
GF_DATABASE_MAX_OPEN_CONN = 10
GF_DATABASE_NAME = grafana
GF_DATABASE_TYPE = postgres
GF_DATABASE_USER =
GF_INSTALL_PLUGINS = michaeldmoore-multistat-panel,grafana-piechart-panel,natel-plotly-panel
GF_REMOTE_CACHE_CONNSTR = <redis_endpoint>
GF_REMOTE_CACHE_TYPE = redis
GF_SECURITY_ADMIN_USER =
GF_SECURITY_ALLOW_EMBEDDING = true
GF_SECURITY_COOKIE_SECURE = true
GF_SERVER_ENABLE_GZIP = true