# Synology Firewall Configuration **URL:** \ **Category:** Help\ **Created:** [February 21, 2024, 2:40am UTC](https://vaultwarden.discourse.group/t/synology-firewall-configuration/3369 "2024-02-21T02:40:15Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![yaotong](https://avatars.discourse-cdn.com/v4/letter/y/9e8a1a/32.png) [@yaotong](https://vaultwarden.discourse.group/u/yaotong)\ **Post date:** [February 21, 2024, 2:40am UTC](https://vaultwarden.discourse.group/t/synology-firewall-configuration/3369/1 "2024-02-21T02:40:15Z")
Hello, I have configured Vaultwarden SMTP and attempted to send a test email. However, I encountered the following error message: “Error sending SMTP test email: SMTP error: Connection error. Failed to lookup address information: Temporary failure in name resolution.” Upon investigation, I discovered that the issue lies with the Synology firewall. After disabling the firewall, the SMTP function worked properly. I attempted to resolve the issue by whitelisting ports 3012 and 8122, but the problem persists. Could someone please advise on how to proceed? Thank you. ---
**Author:** ![TKruzze](https://avatars.discourse-cdn.com/v4/letter/t/3da27b/32.png) [@TKruzze](https://vaultwarden.discourse.group/u/TKruzze)\ **Post date:** [February 21, 2024, 8:54pm UTC](https://vaultwarden.discourse.group/t/synology-firewall-configuration/3369/2 "2024-02-21T20:54:26Z")
Try whitelisting your Docker Bridge Network instead. In my case it’s 172.17.0.0/255.255.0.0. ---
**Author:** ![yaotong](https://avatars.discourse-cdn.com/v4/letter/y/9e8a1a/32.png) [@yaotong](https://vaultwarden.discourse.group/u/yaotong)\ **Post date:** [February 23, 2024, 11:23pm UTC](https://vaultwarden.discourse.group/t/synology-firewall-configuration/3369/3 "2024-02-23T23:23:09Z")
Thank you very much. Following your method, I have resolved the issue.