Hi,
I have an issue with dhcp which I cannot explain.
All my (Maas client) nodes are single nic 10GbE with ipmi sideband on this nic. For security reasons the ipmi is always configured on vlan 4044.
I created 2 scenarios, 1 works as expected, the other which I prefer doesn’t.
All tests are done on Maas 3.1 snap and Maas 3.2 snap.
Scenario 1:
- A physical rackd (single nic)
- untagged traffic for pxe/boot (10.10.15.0/24)
- vlan 100 for regiond traffic
- vlan 4044 for ipmi traffic (10.11.15.0/24)
When configured, it works as expected. With ps I look at the dhcp process and it shows:
/snap/maas/22134/usr/sbin/dhcpd -f -4 -pf /var/snap/maas/common/maas/dhcp/dhcpd.pid -cf /var/snap/maas/common/maas/dhcpd.conf -lf /var/snap/maas/common/maas/dhcp/dhcpd.leases ens1 ens1.4044
dhcp is listening on 2 nics, ens1 and ens1.4044, perfect
Scenario 2:
A vm as a rackd controller, vm has 3 nics
- ens18 regiond traffic
- ens19 pxe/boot (10.10.15.0/24)
- ens20 ipmi (vlan is handled in the switch bridge) (10.11.15.0/24)
ens19 and ens20 both show up as untagged vlan in regiond, I configure dhcp the same as scenario 1
Now pxe/boot works, but ipmi dhcp not. With tcpdump I see the dhcp request from the ipmi/bmc coming in on ens20, but Maas is not servicing them.
With ps it shows:
/snap/maas/19835/usr/sbin/dhcpd -f -4 -pf /var/snap/maas/common/maas/dhcp/dhcpd.pid -cf /var/snap/maas/common/maas/dhcpd.conf -lf /var/snap/maas/common/maas/dhcp/dhcpd.leases ens19
dhcp is not servicing ens20, netstat -tulpn shows dhcp listening on 0.0.0.0:*
When I remove the dhcp scope for pxe/boot on ens19 I see:
/snap/maas/19835/usr/sbin/dhcpd -f -4 -pf /var/snap/maas/common/maas/dhcp/dhcpd.pid -cf /var/snap/maas/common/maas/dhcpd.conf -lf /var/snap/maas/common/maas/dhcp/dhcpd.leases ens20
Now ipmi works, but obviously pxe/boot not anymore
Why is dhcp not able to service 2 subnets in the same vlan? I have isc servers where this work for many nics at the same time.
Is my thinking wrong here?
Thanks