"Dial out" for the target to register with an NMS and publish pre-configured subscriptions

[hesingh]

For future work, I see the feature listed in the title of this issue. Nobody cares about IPv4 in the data center (DC) now. More information would be useful. For example, IPv6 creates a link-local address when the interface is up. Is the expectation that each link-local domain includes a NMS for a target to register with? Which open-source NMS would we change first for the dial out feature?

Or if target interface uses DHCPv6, the IPv6 global address of a NMS could be provided as DHCPv6 option and then the target registers with NMS.

thanks,

Hemant

[robshakir]

Hi Hemant,

We have some design proposals for dial-out that are currently being worked on.

However, I'm not sure that your point of "no-one cares about IPv4" is incompatible with dial-in. It is very likely that for a number of applications one still wants some stable way to manage a device -- there is no reason that a system cannot have a dial-in IPv6 address (be it auto-configured, or assigned by DHCPv6). This then allows a collector or config management system to dial in to the target by knowing the DHCPv6/SLAAC address.

We will likely support dial-out in the reference collector in github.com/openconfig/gnmi as cmd/gnmi_collector.

Thanks, r.

[hesingh]

Hi Rob,

Appreciate the quick reply. Thanks for the github reference as well. When the design proposals for dial-out are sorted out, I'd be interested to look at them. To acquire a SLAAC or DHCPv6 address, IPv6 uses link-local multicast in the network. I hope a data center would be fine with such multicast traffic. Actually, it makes sense to configure an IPv6 address on the target and then dial-out to the NMS to get an IPv4 address. Why have the target use DHCP which uses broadcast messages in the network.

Best,

Hemant

[robshakir]

Sure -- there are definitely cases where dial-out is preferable. I was just making the point that dial-in is not incompatible with IPv6 only datacentre environments. gNMI dial-in works fine in IPv6-only environments.

Cheers, r.

[hesingh]

Ok, got it in regards to dial-in, thanks. Since filing the issue, I found #42 and see gory details on dial-out. Actually, my goal is for a NMS to auto-discover switch targets configured for an IP/IPv6 address. I see dial-out as the only means. I am also a newbie to gRPC and not sure how a client and target setup gRPC between them - I would think each needs to know the IP/IPv6 address of the other before any gRPC messages can be sent. Any presentation on gRPC setup for IP/IPv6 address would be useful for me.

Cheers,

Hemant