CARP interface

[Lutz Donnerhacke]

On Thu, Feb 11, 2021 at 10:27:44AM -0300, Cristian Cardoso wrote:
> I would like to clarify a doubt, if someone has this scenario in the
> use of CARP for the use of virtual ips in interfaces in FreeBSD.
> I have an interface where I have the 10.19.254.2/24 network and I am
> placing the virtual IP 10.19.254.3/32 in the CARP, this interface does
> not have a default gateway, but a static route "10.0.0.0/8 gw
> 10.19.254.1".
> When I activate CARP, the interface stops communicating with IP
> 10.19.254.1 and with that I have no external access on the machine.
> Could anyone tell me if this is the normal behavior of CARP or is it
> not even for scenarios where the interface has static routes?
> I checked the handbook and several manuals over the internet, I didn't
> find anything related to validate my scenario.

That's quite unusal and should not happen. Can you please send me the
relevant rc.conf lines?

Working example here:

cloned_interfaces="${cloned_interfaces} vlan100"
create_args_vlan100="vlan 100 vlandev ixl1"
ifconfig_vlan100="up"
ifconfig_vlan100_aliases="inet 100.115.0.26/17"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 103 advskew 10 pass **** 100.115.0.60/32"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 104 advskew 20 pass **** 100.115.0.61/32"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 105 advskew 30 pass **** 100.115.0.62/32"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 106 advskew 30 pass **** 100.115.0.63/32"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 107 advskew 30 pass **** 100.115.0.64/32"
ifconfig_vlan100_aliases="${ifconfig_vlan100_aliases} inet vhid 108 advskew 30 pass **** 100.115.0.65/32"

resulting in:

vlan100: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=600703<RXCSUM,TXCSUM,TSO4,TSO6,LRO,RXCSUM_IPV6,TXCSUM_IPV6>
	ether d4:f5:ef:26:2f:58
	inet 100.115.0.26 netmask 0xffff8000 broadcast 100.115.127.255
	inet 100.115.0.60 netmask 0xffffffff broadcast 100.115.0.60 vhid 103
	inet 100.115.0.61 netmask 0xffffffff broadcast 100.115.0.61 vhid 104
	inet 100.115.0.62 netmask 0xffffffff broadcast 100.115.0.62 vhid 105
	inet 100.115.0.63 netmask 0xffffffff broadcast 100.115.0.63 vhid 106
	inet 100.115.0.64 netmask 0xffffffff broadcast 100.115.0.64 vhid 107
	inet 100.115.0.65 netmask 0xffffffff broadcast 100.115.0.65 vhid 108
	groups: vlan
	carp: MASTER vhid 103 advbase 1 advskew 10
	carp: BACKUP vhid 104 advbase 1 advskew 20
	carp: BACKUP vhid 105 advbase 1 advskew 30
	carp: BACKUP vhid 106 advbase 1 advskew 30
	carp: BACKUP vhid 107 advbase 1 advskew 30
	carp: BACKUP vhid 108 advbase 1 advskew 30
	vlan: 100 vlanpcp: 0 parent interface: ixl1
	media: Ethernet autoselect (10Gbase-LR <full-duplex>)
	status: active
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>

Routing is done via bird.

Which version of FreeBSD are you using?
FreeBSD ... 12.2-STABLE FreeBSD 12.2-STABLE stable/12-c243266-gd970a8218e1 GENERIC  amd64

I had a similar problem like you with 13-STABLE but was not able to
investigate further. I suspect, that the new routing code is causing this.