Cannot access .local addresses from my iOS devices

Question

I have a computer that is hooked up to my entertainment center that runs an EyeTV media server. I hadn't used it in over a year because we moved and I couldn't pick up any stations, but I bought a new outdoor antenna and now have stuff to watch. I have a bookmark to the server that uses my computer's name (roberts-mac-mini.local) and when I tried to access it from my iPhone 6s, it eventually timed out. This also happens on my iPad Mini.

The thing is, if I use the DHCP address, it works. Also, if I enter roberts-mac-mini.local into Safari on my laptop, it works! It's only when trying to access .local domains from iOS devices that it doesn't work.

Additionally, I cannot ssh via the Terminus app nor can I ping any of my 3 macs using a network utility app using their .local addresses.

Oddly, occasionally, it DOES work, though I have not been able to figure out why.

I just called and spoke to Apple Support. They screen shared with me on my iPhone and I demonstrated how I could access the computer using the DHCP address but not with the .local address. I showed them ping for 2 .local addresses as well. They had me eventually "Reset all settings" on the iPhone and the .local domains all started working for all 3 computers I'm running! It's a pretty drastic fix though. It's going to take me all day going back through my settings and getting everything back to normal. And I'd rather not do this on my iPad. Does anyone know a more nuanced fix to this issue or why it's happening in the first place? I don't want to go back and fix all my settings only to find out that I've re-introduced the issue.

Answer 1

I found an additional workaround after trying the above solutions without luck:

1. On iOS, go to the Wi-Fi settings of the home/office network you are connected to.
2. Go to Configure DNS and set it to manual.
3. Then add the following search domain: .local

After that it immediately started working for me. I just found this solution so can't tell yet if it would stay stable over time but so far it works fine.

Perhaps entering the search domain somehow triggers iOS to actually do the proper DNS lookup request for .local domains. (In my case the local router would come back with the correct internal IP for the domain as I entered it into the LAN DNS settings of the router.)

Answer 2

I figured out a temporary work-around:

• Turn airplane mode on and off

This flushes the DNS cache on the iPhone, which caches DNS resolutions set by Apple's Bonjour, which uses .local for things like airplay and printer service broadcasting.

Once you do this with airplane mode, access to .local addresses on your network should start working, but it's only a temporary fix. Once Bonjour tramples over the DNS settings, it will stop working again. You can repeat this trick to restore access, but for a more permanent fix, you'll just have to use your DHCP-assigned IP address.

If you need .local DNS resolution to work reliably, Apple needs to fix this issue, so I suggest you submit feedback to them.

I blogged about the issue here.

Answer 3

The issue is that .local is not a normal domain name and you should not be using it in a normal DNS

See Wikipedia for a discussion - note that Microsoft have changed their recommendations over time

RFC6762 says

Any DNS query for a name ending with ".local." MUST be sent to the mDNS IPv4 link-local multicast address 224.0.0.251 (or its IPv6 equivalent FF02::FB).

But for small networks you don't actually need a DNS, just use the machine's name and add .local to the end. If all devices have mDNS resolvers installed (which all Apple devices do and the first blog entry explains how to install for Windows and some Linux) then 'it just works'.

If you need DNS for other reasons then don't use .local as a domain but I have seen .internal suggested but there is no defined standard.

Microsoft and similar extracts from the Wikipedia article suggests

Generally, we recommend that you register DNS names for internal and external namespaces with an Internet registrar. This includes the DNS names of Active Directory domains, unless such names are subdomains of DNS names that are registered by your organization name. For example, corp.example.com is a subdomain of example.com. Registering your DNS name with an Internet registrar may help prevent a name collision. A name collision may occur if another organization tries to register the same DNS name, or if your organization merges with another organization that uses the same DNS name.

Several blogs give more readable explanations including https://stevessmarthomeguide.com/multicast-dns/

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