I do not know if I am missing something but the os will not let me Masquerade any subnets larger than /24
Is this a software flaw or is there a reason for this
I have multiple routers with multiple /23 subnets on each router and they masquerade just fine. If you post your config I am sure someone will find what is wrong.
Chances are, your masquerade rule is configured by source address or something, or else you have two LAN segments that aren’t part of the same /23…
e.g. if you have 192.168.1.0/24 and 192.168.2.0/24, you can’t make a NAT rule that masquerades for 192.168.1.0/23
x.x.1.0/23 is not a valid subnet address. x.x.0.0/23 and then x.x.2.0/23 is the next subnet.
Without more information, we can only guess what’s wrong, but in general, if you have a single WAN interface like ether1, then you can masquerade for any arbitrary number of hosts behind it with a single rule:
/ip firewall nat add chain=srcnat out-interface=ether1 action=masquerade
note that there are no IP addresses specified in this rule. This is probably better than specifying source addresses anyway, because no matter what, if a packet goes out this interface, it will only work if the source IP is the interface’s IP, so the simple masquerade handles this completely. If you want to limit who MAY use the interface, then use the filter rules to do that.