Question

[Leslie Rhorer]

On 6/2/2022 11:30 PM, Gregory Sloop wrote:
>
> Are you seeing balance messages every hour as the two re-balance the 
> available lease pool?
>
No, I don't think so.  It has only been a couple of hours since I have 
had both online, however.
>
> You say they are both handling leases properly, but how do you know 
> this? (That a machine gets a lease from somewhere is not good evidence.)
>
     Do you mean because some other machine / device could be issuing 
leases?  No.  In that case,

     1. Killing both servers would not take down any DHCP clients.  If 
both servers are shut down, DHCP clients start failing in about an hour, 
until they are all dead.

     2. DHCP responses on the LAN stop completely the moment both 
servers are taken down.

     3. No other machine would know anything about the list of 
dynamically assigned fixed IP addresses in dhcpd.static.  None of the 
addresses of any of the clients ever change.

     4. Whenever one server is shut down, the other responds with tons 
of responses in  the log.

> A packet capture in front of the secondary might be helpful to see 
> what traffic is passing - both to the peer and to clients.
>
     While not impossible, that is a bit easier said than done.  The 
links between the servers are 10G.  I can look into it.
>
> (I hate making captures, at least as much as the next person, but dang 
> if they don't, nearly always, show something that was different than I 
> assumed. So, I've just gotten a lot less averse to getting captures. 
> Yeah, they'll probably take me extra time to setup and get and paw 
> through, [all when I could be fixin' stuff!] but they can save hours 
> or days of fruitless searching for a fix, when I don't even really 
> *know* what's wrong yet. Don't know about anyone else, but fixing 
> problems gets a whole lot easier when I actually know what's wrong, or 
> at least have a good idea what's going on. :)
>
     Agreed, although when an interface is chunking away at over 10,000 
packets per second...

     If something doesn't break loose, I will see about loading Wireshark.
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