Configure outgoing mail on Redash

Installing Redash is straightforward if you use https://github.com/getredash/setup repository. Just run setup script to download, install and configure all required packages. But there is one thing missing from the default. It is mail configuration. First install Redash with all default settings and then edit /opt/redash/env file:

REDASH_MAIL_SERVER
REDASH_MAIL_PORT
REDASH_MAIL_USERNAME
REDASH_MAIL_PASSWORD
REDASH_MAIL_DEFAULT_SENDER
REDASH_USE_TLS = true
REDASH_USE_SSL = false
REDASH_HOST

After setting those values run docker-compose up -d command to recreate containers. Use TLS and local IP address if you host your mail server on-premise. Now you should be able to send mail messages from your Redash.

Private Docker Registry with pfSense-offloaded TLS connections

Benefit from running your own docker registry is cost and privacy. But in order to use it in various places you need to secure its connection with SSL/TLS certificates. In case you have only ZeroSSL or LE certificates it can be difficult to maintain both you certificate at ACME/HAProxy leve in pfSense and secondary also in docker registry somewhere else.

Fortunately there is solution for that.

Add your docker registry domain to ACME certificate enrollment as usual. Run docker registry without giving it certificate. Instead configure a domain pointing at pfSense, preferably using non-WAN address. Next configure proxy-pass at Nginx level:

server {
  listen 80; 
  server_name registry.somedomain.com;
  ignore_invalid_headers off;
  client_max_body_size 0;
  proxy_buffering off;
 
  location / {
    access_log  /var/log/nginx/registry-somedomain-com.log;
    proxy_set_header Host $http_host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto https;
    chunked_transfer_encoding off;
    proxy_pass http://a.b.c.d:5000/;
  }
}

Most important part of it is to set X-Forwarded-Proto to https. Now you can use docker registry which runs locally and forget about setting up certificate renewal at registry level itself.

Proxmox LXC backup with exit code 11

In case you have some LXC containers on your Proxmox server, then there is high chance that you will get some errors during backup them up. Some container templates may not support snapshot or suspend modes. Instead you should you use stop mode. It is important to remember that during such backup container will be stopped, so be aware of that in case you have some encryption which could ask for a key during startup.

Germany BSI abuse message prevention

In case of an Abuse message from BSI (in Germany), the following services must be enabled and disabled:

systemctl disable rpcbind.target
systemctl disable rpcbind.socket
systemctl disable rpcbind.service
systemctl stop rpcbind.target
systemctl stop rpcbind.socket
systemctl stop rpcbind.service

Verify in 2 ways:

rpcinfo -T udp -p 192.168.45.67

telnet 192.168.45.67 111

Cutting with DROP traffic by Suricata IPS is not sufficient, because not all possible traffic signatures on port 111 are used and in most cases this port can be enumerated.