I used Apache proxy a very long time, but some guys have reported that Nginx is faster (or better). However therefore I changed my configurations from Apache to Nginx which is very similar.

Nginx proxy documentation and Google helped a lot.

Here is a piece out of my conf file:

# Fix the “It appears that your reverse proxy set up is broken" error.
proxy_pass https://<your server ip>;

So it is really that simply. The only thing you have to check for Filr is download/upload limits. Nginx default values are not really high - 10 MB or similar if I remember.

I use Nginx for all my access paths - GroupWise, Filr, Retain, SMG, Vibe,... and much more. The only product which is hard to configure is Content Editor. But if you check the community here you will find the solution 

That much more easy indeed.
Question : Due to licensing my vm is OES2023. Can I just install nginx ? Or does that Fubar the entire OES system ?

I keep it as small and simple as possible. Therefore it is a small Sles15 (low memory). I use my GW - sles license for this proxy server. Usually there should be a Sles license for your GW server(s) because you are allowed to run your GW system on Sles.

Nevertheless Nginx should run on OES too. However your proxy server does not need any OES features  (I know you want to use the license only ).

If you want to experience a little more excitement then go for the docker nginx version ...

Hi there!, how are you. I have a few customers using HAproxy for Filr. For your reference I'm attaching the /etc/haproxy/haproxy.cfg of one of my customers. 

Hope this help you!. Best regards from Bs.as - Argentina ;-)

### Filr LoadBalancer
global
# log 127.10.0.1 local0 info
log /dev/log local0 debug
pidfile /var/run/haproxy.pid
maxconn 6000
daemon
user haproxy
group haproxy
tune.ssl.default-dh-param 2048

### Default settings
defaults
log global
timeout connect 30s
timeout client 90s
timeout server 90s
option dontlognull
option log-health-checks
option http-server-close
timeout http-request 5s
timeout queue 2m
timeout http-keep-alive 180s
timeout check 10s
### Redispatch Enable or disable session redistribution in case of connection failure
option redispatch
option clitcpka

frontend Filr_Frontend80
bind :80
mode http
reqadd X-Forwarded-Proto:\ http
rspadd Strict-Transport-Security:\ max-age=31536000
default_backend Filr-Servers

frontend Filr_Frontend443
bind :443 ssl crt /etc/ssl/private/mobility.pem ciphers EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5:!RC4 no-sslv3 no-tlsv10
mode http
reqadd X-Forwarded-Proto:\ https
rspadd Strict-Transport-Security:\ max-age=31536000
default_backend Filr-Servers

frontend Filr_Frontend8443
bind :8443 ssl crt /etc/ssl/private/mobility.pem ciphers EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5:!RC4 no-sslv3 no-tlsv10
mode http
reqadd X-Forwarded-Proto:\ https
rspadd Strict-Transport-Security:\ max-age=31536000
default_backend Filr-Servers

backend Filr-Servers
mode http
# log /dev/log local0 debug
#mode tcp
balance roundrobin
stick-table type ip size 1m expire 10m
stick on src # probar att skippa # cbonte.github.io/.../configuration-1.5.html
server filr-applan1 192.168.135.11:80 check
server filr-applan2 192.168.135.12:80 check
server filr-applan3 192.168.135.18:80 check
server filr-applan4 192.168.135.19:80 check

backend all_the_things
server filr-applan1 192.168.135.11:8080 check
server filr-applan1 192.168.135.11:8443 check
server filr-applan2 192.168.135.12:8080 check
server filr-applan2 192.168.135.12:8443 check
server filr-applan3 192.168.135.18:8080 check
server filr-applan3 192.168.135.18:8443 check
server filr-applan4 192.168.135.19:8080 check
server filr-applan4 192.168.135.19:8443 check
server filr-netsync 192.168.135.17:9443 check
server filr-netsync 192.168.135.17:8443 check
server filr-search1 192.168.135.13:1199 check
server filr-search2 192.168.135.14:1199 check
server filr-sqldb1 192.168.135.15:5432 check

#Monitor
listen stats
bind :6080 ssl crt /etc/ssl/private/mobility.pem ciphers EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5:!RC4 no-sslv3 no-tlsv10
mode http
option forwardfor
option httpclose
stats enable
stats hide-version
stats refresh 10s
stats show-desc Filr Backends
stats show-legends
stats realm HAProxy\ Statistics
stats auth root:xxxxxxxx
stats uri /stats
stats scope Filr-Frontend
stats scope Filr-Servers
stats scope all_the_things
stats scope stats
stats refresh 20s