203.0.113.25
, specify 203.0.113.25/32
to list this single IPv4 address in CIDR notation. If your company allocates addresses within a range, specify the entire range, such as 203.0.113.0/24
.0.0.0.0/0
, it will enable all IPv4 addresses to access your instance using SSH.us-east-1a
, us-east-1b
, us-east-1c
, us-east-1d
, or us-east-1f
.