It occurs to me Tony, there could be a multitude things here. But one involves routes and routing tables. Presuming the two networks on your multi-homed HMC don't overlap (different subnets) I'd wonder how your routes in that box are set up (default and otherwise).
#3 concerns me a little that you have the same Mac arp resolution to 2 different IPs. While not impossible there could be some issues with this. Have you captured the traffic from the host that is suspect - and rebooted, see if it is actually dhcp requesting an address? It sounds like there could possibly be another box with a MAC address the same as your HMC. That's one idea. or a process on it requesting a dhcp address. If it were me I'd take two traffic captures, one that gets all the traffic from the HMC you suspect. and one from the box handing out IPs. Do a reboot of the HMC if you can, and see if the traffic coincides with expected behavior. That's where I'd start. Chad > On Nov 20, 2015, at 23:03, Tony Thigpen <[email protected]> wrote: > > Background: HMC software version 2.11.1 connected to a z10. > > The HMC is connected to two networks. The first is a small private network > with just the laptops in the z10 and the HMC. No other HMCs or other CPUs. > The second network is a local network with several items on it, including > other HMCs. This network is behind a VPN firewall and is used to access the > web services on the HMC. > > Both interfaces have hard-coded IP addresses. > > Today we noticed something strange. We had a DHCP address assigned to a box > we did not know about. Except for 3 workstations on the network, all other > boxes have hard-coded IP addresses. In the DHCP assigned addresses table, the > box had provided a name of BMC_DHCP. > > After a bunch of testing, we isolated the assigned address to the HMC, but > the address does not show up in any of the HMC panels that show IP addresses. > > Items: > 1) When we ping the HMC using the hard-coded address, the response is under > 3.0ms. > 2) When we ping the DHCP assigned address, the response is 10x longer, in the > 30.0ms range. > 3) The arp tables on another PC show both addresses having the same nic > address. > 4) The HMC can ping it's own hard-coded address, but it can not ping the DHCP > assigned address. > 5) We have other CPUs and other HMCs. None of the others are doing the same > thing. (z900 though z10). > 6) This HMC has the latest software version of all the HMCs. > 7) nMap (port mapping tool) says that there are no ports open at this DHCP > assigned address. > > Thoughts on what is happening? > Anybody else seeing the same thing? > > -- > Tony Thigpen > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
