diff --git a/inventories/chaosknoten/hosts.yaml b/inventories/chaosknoten/hosts.yaml
index 1028deb..082a76a 100644
--- a/inventories/chaosknoten/hosts.yaml
+++ b/inventories/chaosknoten/hosts.yaml
@@ -67,9 +67,9 @@ all:
       ansible_user: chaos
       ansible_ssh_common_args: -J ssh://chaos@public-reverse-proxy.hamburg.ccc.de
     sunders:
-      ansible_host: sunders-intern.hamburg.ccc.de
+      ansible_host: sunders.hosts.hamburg.ccc.de
       ansible_user: chaos
-      ansible_ssh_common_args: -J ssh://chaos@public-reverse-proxy.hamburg.ccc.de
+      ansible_ssh_common_args: -J ssh://chaos@router.hamburg.ccc.de
     renovate:
       ansible_host: renovate-intern.hamburg.ccc.de
       ansible_user: chaos
diff --git a/resources/chaosknoten/public-reverse-proxy/nginx/acme_challenge.conf b/resources/chaosknoten/public-reverse-proxy/nginx/acme_challenge.conf
index 409b5c6..f02a657 100644
--- a/resources/chaosknoten/public-reverse-proxy/nginx/acme_challenge.conf
+++ b/resources/chaosknoten/public-reverse-proxy/nginx/acme_challenge.conf
@@ -29,7 +29,7 @@ map $host $upstream_acme_challenge_host {
     wiki.hamburg.ccc.de wiki.hosts.hamburg.ccc.de:31820;
     www.hamburg.ccc.de 172.31.17.151:31820;
     tickets.hamburg.ccc.de 172.31.17.148:31820;
-    sunders.hamburg.ccc.de 172.31.17.170:31820;
+    sunders.hamburg.ccc.de sunders.hosts.hamburg.ccc.de:31820;
     zammad.hamburg.ccc.de 172.31.17.152:31820;
     eh03.easterhegg.eu 172.31.17.151:31820;
     eh05.easterhegg.eu 172.31.17.151:31820;
diff --git a/resources/chaosknoten/public-reverse-proxy/nginx/nginx.conf b/resources/chaosknoten/public-reverse-proxy/nginx/nginx.conf
index 97e0e3c..90ec655 100644
--- a/resources/chaosknoten/public-reverse-proxy/nginx/nginx.conf
+++ b/resources/chaosknoten/public-reverse-proxy/nginx/nginx.conf
@@ -43,7 +43,7 @@ stream {
         staging.hamburg.ccc.de 172.31.17.151:8443;
         spaceapi.hamburg.ccc.de 172.31.17.151:8443;
         tickets.hamburg.ccc.de 172.31.17.148:8443;
-        sunders.hamburg.ccc.de 172.31.17.170:8443;
+        sunders.hamburg.ccc.de sunders.hosts.hamburg.ccc.de:8443;
         zammad.hamburg.ccc.de 172.31.17.152:8443;
         c3cat.de 172.31.17.151:8443;
         www.c3cat.de 172.31.17.151:8443;
diff --git a/resources/chaosknoten/sunders/nginx/sunders.hamburg.ccc.de.conf b/resources/chaosknoten/sunders/nginx/sunders.hamburg.ccc.de.conf
index 04cc006..ceb9b2b 100644
--- a/resources/chaosknoten/sunders/nginx/sunders.hamburg.ccc.de.conf
+++ b/resources/chaosknoten/sunders/nginx/sunders.hamburg.ccc.de.conf
@@ -2,7 +2,7 @@
 # https://ssl-config.mozilla.org/#server=nginx&version=1.17.7&config=intermediate&openssl=1.1.1k&guideline=5.6
 server {
     # Listen on a custom port for the proxy protocol.
-    listen 8443 ssl http2 proxy_protocol;
+    listen [::]:8443 ssl http2 proxy_protocol;
     # Make use of the ngx_http_realip_module to set the $remote_addr and
     # $remote_port to the client address and client port, when using proxy
     # protocol.