.local is a standard. Its a part of mDNS (multicast DNS). Dont use it for your own DNS records.
I'm not sure what exact issue you are having, but if you are trying to resolve mDNS .local across internal networks then you need to look up mDNS reflection. If you are trying to use .local for your own DNS records then pick something else (ideally using an actual registered TLD, so e.g. if you own foo.com then you could use lan.foo.com for your internal records).
I'm not sure what exact issue you are having, but if you are trying to resolve mDNS .local across internal networks then you need to look up mDNS reflection. If you are trying to use .local for your own DNS records then pick something else (ideally using an actual registered TLD, so e.g. if you own foo.com then you could use lan.foo.com for your internal records).