Auto Dependency question...

Our network, while very large, is actually made up of a small number of patterns repeating hundreds or thousands of times

e.g.

a building will have a distribution switch-stack, with LAGS connecting edge switches to it [500 cases, 4,500 switches)

I'm not sure that part of our network design is very unusual

I tried turning on auto dependency and it kind of got a VERY random selection right, but in other cases it put dependencies between edge switches (which are not directly connected to each other)

Could someone point me to a technical description of how the auto-dependency generation will work

if I leave it turned on, and send in diagnostics has anyone had help from support to 'fix' whatever is broken in this?

[I could write code to add the right dependencies, but this is thousands of dependencies and why buy a tool when you have one already]

thanks

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rschroeder

I have auto-dependency enabled, and in addition to the manual Parent-Child relationships I've built, I see it's done a partial build of other valid relationships. However, it's not always thorough, nor complete, although it IS pretty accurate most times.

Suppose a site has a router, a distribution stack, multiple access stacks using port-channels off the distribution stack, and multiple devices attached to the access stack.

Ideally I expect all discovered devices attached to the access stack would be in a group dependent on that stack.

And all the Access stacks would all be dependent on the Distribution stack.

And the Distribution Stack is dependent to the Router.

I don't always see that. How do CDP and LLDP play roles in all this? If only CDP is a player, AP's would be Children of Access Switches, which are Children of Distribution Switches, which are Children of the Router. But that's not happening. Sometimes routers are chosen by Auto-Dependency to be the Parent, but sometimes UPS's are. That's not right.

I'll be watching this thread for more knowledge, and I hope to dig deeper into how automatic Dependencies are created.

squinsey

Indeed very valid question Richard,

As a MSP we leave it off - unfortunately we get joins all over the place as well. (wild guess) but
Probably due to our security governance policy not allowing CDP to be running,
And/or the whole device routing table being looked at for the relation discovery and connected to near matches of IP address'

We manually join the dots via arp cache etc and diagrams as a new site is completed.

Manual pain but most of it is probably due to our policies. Our device naming convention atleast helps the keep the murky water a bit clear when used with a diagram.

sitename-floornumber-r01 (or cs01 / sw01 / st01)

Might need to add to that NTM wish list for discovery methods, and dependency calculations for NTM and NPM to use.

RichardLetts

We have LLDP enabled everywhere (not really a cisco shop, even though we have 400+ cisco routers), and as far as I can see it (LLDP) is not being used...

Observations...

given our very simple topology in buildings I can think of several strategies that produce the right topology. the simplest one (non-recursive) is

find nodes that are root bridges; make them the parent-candidates;

for all other nodes if they have a parent-candidate as a root bridge make them depend on that

What I think I am missing in the dependency UI is the answer 'Why' -- why was /this/ particular relationship chosen.

It might be that unexpected results in the autodependency are really indicating some misconfiguration in the network, but since I can't easily figure out why a particular relationship was chosen I can't fix it.

if I know the rules for autodependency generation then I know where to start troubleshooting it.

RichardLetts

I'm gathering diagnostics and opening a support case.

Really like I can exclude UDT, NCM, and wireless data from the just-updated SolarWinds Diagnostics which will shrink the diagnostics by a lot,

Also like that it's generated a nice unique name for the diagnostics file.

maciej.sandecki

Hi Richard,

5 years later and I'm in the same place as you were with same auto-dependency issues. I haven't opened a support case yet, but I'm about to do this. Did you get this resolved for your installation?

Thanks in advance!