Caching server not working (El Capitan server)

Hi Omid,

We have the same problem. Trying to put this working in an ISP environment. The cache server is located in a public ip, different from the users.

It is used a domain for reverse dns of each user. The txt record with prs=x.x.x.x-x.x.x.y was included in DNS configuration of the public domain.

But no success.

What are we doing wrong ?

Thanks

the IP was changed to a static in the 10.0.10.x scope

Have you changed your whole network over to that netblock? If not, the Caching Service won't work.

Please search the clients for log messages from AssetCacheLocatorService. A normal message looks like this:

[I:AssetCacheLocatorService.queue] found caching server on ip-address:port

Does your organization have more than one public IP address, i.e. to load balance across multiple ISPs?

Search the caching server's log file for "Registering with" and "public IP" and make sure that info looks correct:

$ egrep "Registering with|public IP" /Library/Server/Caching/Logs/Debug.log

On a Mac or iOS device that you think should be using that caching server, open Safari and navigate to http://www.whatsmyip.net/ or any other site that will reveal your public IPv4 address. Does the IPv4 address it shows match the public IP address of the caching server above?

If the "Registering with" line shows a range of local addresses, check the network settings on the other Mac or iOS device. Does its local address lie within the range?

I have the problem which you described . My server's public ip is x.y.z.206 but our company security policy force the server to connect through proxy server to outside . Now the "Registering with|public IP" shows proxy server ip instead of x.y.z.206 . The proxy server ip does not belong to us and i have no permission on it .

Is there a way to register with proxy server ip but use server own ip for caching ?

If your devices also connect through the same proxy, it should all work because the clients and the server will have the same public address, namely, the proxy's address. Otherwise, configure both public IP addresses in Server > Caching > Permissions: Edit Permissions... > Serve clients with public addresses:, and set up a DNS TXT record to match; see the Client Configuration... button on that same page. Be sure to enter only public addresses there, and not any private 10.x.x.x, 172.16.x.x-172.31.x.x, or 192.168.x.x addresses.

Thanks for reply .

So you mean the "Registering with|public IP" is not the ip address which serves the cache ? Then the only way that it will find the real ip of server should be DNS txt record part of configs. right ?

Also is it possible to take a look to my other thread please Caching service usable for isp ?

You can think of a computer (including a Mac running Server, and an iOS device) behind a NAT as having two addresses: a private (or "local") address on the immediate NATted network, and a public address visible to the Internet. Private addresses are almost always 10.x.x.x, 172.16.x.x-172.31.x.x, or 192.168.x.x. Public addresses are assigned to you by your ISP.

Computers and devices ("clients") on your NATted network search for caching servers by asking an Apple cloud service for them. The cloud service matches up clients with registered caching servers using public addresses (or public address ranges, if you have more than one public address). If you have more than one caching server behind the same public address, the cloud service uses the local address of the client to choose one of them.

If you have just one public IP address that both your caching server(s) and your client(s) share, it all works out of the box. The caching server(s) register with their local address(es) and the one public address automatically. The client(s) look up caching servers using the same public address, also automatically. The cloud matches them up and instructs the clients to use whichever caching server is configured for the local network the client is on.

If you have more than one public IP address, though, the caching server has to register for all of them. That's why you have to enter them all in the Server app. Clients have to match caching servers on the same public IP addresses, so you have to set up a DNS TXT record available to all clients so they have that info. The matching happens as above but with ranges of public addresses instead of single public addresses.

I'm not sure that answers your question but I hope it helps. Can you be more clear about what you mean by the "real ip of the server," given that servers (and clients) have both private and public addresses?

Thanks for reply .

The public ip of macOS server is 1.1.1.206 but since it connects through a proxy server , it will register with proxy server's ip 5.6.7.8 to apple servers . So i think when clients request the update from apple servers , apple servers will send 5.6.7.8 as Cache server which is fault .

Is there a way to say to apple servers that the REAL public ip of my server is 1.1.1.206 even if it is behind proxy ?

In your diagram, your clients and your caching server all have two routes to the Internet: one through the proxy and one without. If your clients and your caching server always route through the proxy, caching should work automatically with default settings because the clients and the server have the same public address 5.6.7.8, and clients will be told to download from the caching server at local address 1.1.1.206. But if your clients and your caching server route to the Internet in different ways, they might have different public (Internet-facing) addresses: sometimes 5.6.7.8, sometimes the unnumbered link in your diagram directly from the router to the Internet. In that case you will need to configure the caching server and a DNS TXT record for both public addresses.

Only servers route through the proxy . Also the users ip are not unnumbered , they are for example 1.1.2.0/24 and 1.1.3.0/24 (written in image maybe bad place) .

The DNS TXT records implemented for 5.6.7.8,1.1.1.206,1.1.2.0/24,1.1.3.0/24 and tested.

Please run to check real config with real IPs.

nslookup -type=txt _aaplcache._tcp.shabdiznet.com

Thanks

Perhaps I misunderstood. Is the router in your diagram performing NAT or not?

If your router does perform NAT then your caching server and your DNS TXT record need to specify only the public (Internet-facing) addresses, and not any addresses behind your NAT router (which are local addresses). The only public addresses are 5.6.7.8 and the address your ISP assigns to your router for the link in your diagram that does not go through the proxy but connects the router to the Internet. You do not need to add local addresses 1.1.1.206, 1.1.2.0/24, or 1.1.3.0/24 to your caching server's public address configuration or your DNS TXT record.

However if your router does not perform NAT then all of your clients and your caching server use public addresses. In that case your caching server configuration and DNS TXT record need to specify the addresses of all the clients and the proxy, but not the caching server's address 1.1.1.206 because it routes through the proxy.

Incidentally, your DNS TXT record does not need to be accessible from the Internet. It only needs to resolve inside your network.