RT2600AC Router Setup Notes

There are a few obscure customizations I make to my router over SSH that I’m documenting here so I can remember how to do them in the future.

Getting SSH root

The admin account needs to be enabled in the router management web portal, then it can be used over SSH as a root user.

Enabling multiple IPv6 prefixes via DHCPv6-PD

The post here helped me figure out how to get my router to request a different IPv6 prefix length from my ISP, per @jazzyj:

I found you can edit the /etc/init/dhcp-client6.conf file to include a prefix hint for the DHCPv6-PD setup, line 43:

For me, this was the resulting diff in /etc/init/dhcp-client6.conf:

@@ -40,7 +40,7 @@
                        exec /usr/sbin/dhclient -6 -d -q -pf ${PID_FILE} -lf ${LEASE_FILE} -cf ${CONFIG_FILE} -nw ${IFACE}
-                       exec /usr/sbin/dhclient -6 -d -q -pf ${PID_FILE} -lf ${LEASE_FILE} -cf ${CONFIG_FILE} -P -N -nw ${IFACE}
+                       exec /usr/sbin/dhclient -6 -d -q -pf ${PID_FILE} -lf ${LEASE_FILE} -cf ${CONFIG_FILE} -P --prefix-len-hint 60 -N -nw ${IFACE}

Now my ISP assigns me 8 IPv6 prefixes I can assign to a bunch of different subnets.

Dynamic Porkbun DNS

I have a hacky shell script I run periodically to update DNS records to point my domain name at my public IP address.

The script itself can be found here.

I store it in /volume1/my_scripts (since apparently it is safe from being wiped during updates) and add it to /etc/crontab as follows:

#minute hour    mday    month   wday    who     command
0       */3     *       *       *       root    /volume1/my_scripts/

Afterwards, just restart crond with the following command:

synoservicectl --restart crond