Problems of using secondary router without bridge mode

[netomato]

I want to know is there any problem to use secondary, tertiary or more routers connected to the main router without setting it in bridge mode?

What are the pros and cons?

 

[wheatbread]

Which router 'it' is referring to?
You probably want 'secondary' routers to be an extension of your existing network rather than a separate network. This is also crucial for native IPv6 to work.

 

[Lolita_Magnum]

No real cons and definitely no pros. It's a modern curse in the networking world that is just pure filth.
You are just doing port address translation over an already existing port address translation.
Bridge is just making a port switch into Layer-2 mode. There is no packet overhead for NAT; your 1372 bytes of data per packet will still be the same regardless of how many NATs you do.
Residential Customers want bridge so they can have control or rather more fine-tuning over the Service Provider IP (public or private) that have been assigned instead of being slave to the ISPs locked down router.
If you are already being provided a CG-NAT-ed IP for your LAN-to-WAN; regardless of if you bridge or not, it won't make a difference.
If you receive a Public IP and you NAT; it increases the chance of breaking TCP-keep alive connections (this is true regardless of if you single NAT or Double NAT), but this is only important if you host a high traffic server and judging by the ever-increasing cloud; it is quite obvious the industry does not want you to host stuff from your home.

 

[JB701]

@netomato NAT does have some overhead (varies from device to device). You should set it in AP mode.

 

[netomato]

Thanks for the answer guys, I usually download/upload heavy stuff and apart from it I don't do any hosting or any sort of technical work. And this system has been working fine for me since many years. As per your reviews I think I have no problem in it. I am behind CG-NAT.