# Link with another ngIRCd server

## Before you begin

In this guide, we assume [ngircd](ngircd/install) has been installed and configured to support [[SSL](/ngircd/ssl).
In this guide, we assume [ngircd](ngircd/install) has been installed and configured to support [[SSL](/ngircd/ssl).

## Updating the Configuration

Suppose you have two servers that you want to link together: `irc.example.com` with IP address 192.0.2.1 and `irc.network.org` with IP address 198.51.100.1.

**NOTE**: In your own configuration, you must replace these values with real hostnames and IP addresses.

Edit the `[Server]` block in `/etc/ngircd/ngircd.conf` in `irc.example.com`:

    [Server]
    	Name = irc.network.org
    	Host = irc.network.org
    	Bind = 192.0.2.1
    	Port = 16697
    	MyPassword = IRCEXAMPLECOMPASSWORD
    	PeerPassword = IRCNETWORKORGPASSWORD
    	Group = 123
    	Passive = yes
    	SSLConnect = yes
            ;ServiceMask = *Serv,Global


Make sure the [Server] block is not commented.

Notice that for `irc.example.com`, the other hostname, `Host = irc.network.org` (the other server) is used. If possible, we recommend using a [symbolic hostname](/dns/overview) for Host rather than an IP address. That way, if the IP address changes in the future, the conf file does not need to be updated. So, we use `Host = irc.network.org` and not an IP address like `192.0.2.1`.

Bind should be set to the public IP address for `irc.example.com`. If you have a [DDoS-filtered IP](/ddos/intro), you should use it. We recommend using an IPv4 address because IPv6 can be less reliable.

MyPassword for `irc.example.com` (this server) must match the PeerPassword for `irc.network.org` (the other server), and PeerPassword for `irc.example.com` must match MyPassword for `irc.network.org`.

You must replace `IRCEXAMPLECOMPASSWORD` and `IRCNETWORKORGPASSWORD` with [strong passwords](/password/management).

These passwords are stored in cleartext (not hashed) so we recommend you generate a new password.

Port 16697 with SSL is recommended to keep the connection secure and to avoid having traffic on port 6697, which is normally used by users to connect to the IRCd. Set SSLConnect to yes.

ngIRCd allows server groups. Only one direct link will be formed

with servers with the same group ID.

One server should have `Passive = yes`, and the other should have `Passive = no`. If using a hub and spoke model, a useful convention is for hubs to have `Passive = yes`, and leaf nodes `Passive = no`.

SSL should be used to prevent sensitive information being sent in plaintext.

Next, edit `/etc/ngircd/ngircd.conf` in `irc.network.org`. If you do not control this server, you will need to ask the other admin to edit it.

[Server]

	Name = irc.example.com

	Host = irc.example.com

	Bind = 198.51.100.1

	Port = 16697

	MyPassword = IRCNETWORKORGPASSWORD

	PeerPassword = IRCEXAMPLECOMPASSWORD

	Group = 123

	Passive = yes

	SSLConnect = yes

        ;ServiceMask = *Serv,Global

## Autostart

To automatically restart ngIRCd if it was terminated unexpectedly, create a script in /usr/local/libexec/project/ngircd.sh:

    doas touch /usr/local/libexec/project/ngircd.sh
    doas chmod +x /usr/local/libexec/project/ngircd.sh


Inside /usr/local/libexec/project/ngircd.sh:

    #!/bin/sh
    SERVICE_NAME="ngircd"
    SERVICE_USER="_ngircd"
    SERVICE_PID="/var/ngircd/var/run/ngircd/ngircd.pid"
    if # pgrep -u $SERVICE_USER -x "$SERVICE_NAME" > /dev/null
    then
      if [ -f $SERVICE_PID ]; then
        rm -f $SERVICE_PID
        rcctl -d start $SERVICE_NAME
      fi
    fi


Add this as a cronjob:

    $ doas crontab -e
    *       *       *       *       *       /usr/local/libexec/project/checker_ngircd.sh > /dev/null 2>&1


For the solution to work, you need to enable the use of pid files in /etc/ngircd/ngircd.conf:

    PidFile = /var/run/ngircd/ngircd.pid


Make sure to configure [hopm](/hopm/install).