https://github.com/docker/docker/issues/866?source=c
> Missing the 'nat' table is a symptom of missing kernel modules.

task: rebuild iptables kernel modules since I have a custom kernel

https://github.com/docker/docker/issues/866?source=c#issuecomment-43093182
> I was missing IP_NF_TARGET_MASQUERADE in my kernel config.

$ make menuconfig
Location:
-> Networking support (NET [=y])
   -> Networking options
      -> Network packet filtering framework (Netfilter) (NETFILTER [=y])
         -> IP: Netfilter Configuration
            -> IP tables support (required for filtering/masq/NAT) (IP_NF_IPTABLES [=m])
               -> iptables NAT support (IP_NF_NAT [=n])                                                                                                

iptables NAT support
- MASQUERADE target support
- NETMAP target support
- REDIRECT target support