I suspect the MAC address you see inside the jail with ifconfig is also used by some other VM connected to the same vSwitch. Or by the TrueNAS host but you already ruled that out.
The host complains that the MAC address that it saw on the epair (the host end, named vnet0.1) was suddenly appearing on vmx0 - which goes to the vSwitch …
Hmm I can’t see anything, here is the switch topology
Anychance it’s residual config on vmx0? I didn’t see any assigned mac address to remove when executing your original steps
Maybe something with those dual uplinks. Are they connected to a managed switch and run LACP?
Topping it off jails can’t reach the default gateway again so back to square one.
I did create a new jail and shut off the old one for now so I’m working with a fresh jail on version 13.5 to isolate existing config as an issue. I still see the MAC address log but the DAD one is gone indicating that was an issue on the original jails config (I think unable to disable ip6 autoconfig for some reason). Hoping I can transfer files from original jail or use the settings that work from the new one to get the old jail functional. Worst case I can abandon the original and rebuild the media library metadata (plex)
Uplinks are the ports on my server board, afaik designed to both be connected https://www.asrockrack.com/general/productdetail.asp?Model=E3C246D2I#Specifications
host ifconfig
root@freenas[~]# ifconfig
vmx0: flags=8963<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
description: vmx0
options=8000b8<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM>
ether 00:0c:29:05:1b:d2
media: Ethernet autoselect
status: active
nd6 options=9<PERFORMNUD,IFDISABLED>
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
options=680003<RXCSUM,TXCSUM,LINKSTATE,RXCSUM_IPV6,TXCSUM_IPV6>
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x2
inet 127.0.0.1 netmask 0xff000000
groups: lo
nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
pflog0: flags=0<> metric 0 mtu 33160
groups: pflog
bridge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
ether 58:9c:fc:10:ff:9c
inet 192.168.50.212 netmask 0xffffff00 broadcast 192.168.50.255
id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15
maxage 20 holdcnt 6 proto rstp maxaddr 2000 timeout 1200
root id 00:00:00:00:00:00 priority 32768 ifcost 0 port 0
member: vnet0.1 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
ifmaxaddr 0 port 5 priority 128 path cost 2000
member: vmx0 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
ifmaxaddr 0 port 1 priority 128 path cost 2000
groups: bridge
nd6 options=9<PERFORMNUD,IFDISABLED>
vnet0.1: flags=8963<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
description: associated with jail: test as nic: epair0b
options=8<VLAN_MTU>
ether 5a:9c:fc:ae:1b:75
hwaddr 02:0e:62:d8:3f:0a
groups: epair
media: Ethernet 10Gbase-T (10Gbase-T <full-duplex>)
status: active
nd6 options=9<PERFORMNUD,IFDISABLED>
jail ifconfig
root@test:~ # ifconfig
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
options=680003<RXCSUM,TXCSUM,LINKSTATE,RXCSUM_IPV6,TXCSUM_IPV6>
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
inet 127.0.0.1 netmask 0xff000000
groups: lo
nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
pflog0: flags=0<> metric 0 mtu 33160
groups: pflog
epair0b: flags=8863<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
options=8<VLAN_MTU>
ether 5a:9c:fc:ae:1b:76
hwaddr 02:0e:62:d8:3f:0b
inet 192.168.50.214 netmask 0xffffff00 broadcast 192.168.50.255
groups: epair
media: Ethernet 10Gbase-T (10Gbase-T <full-duplex>)
status: active
nd6 options=1<PERFORMNUD>
Unplug one port please and test again.
no change with the second port unplugged.
edit: witht he logs at least but the jail connects correctly so it seems ytou are right in that it relates tot eh dual uplink. It has never been an issue previously but I guess truenas upgrade must’ve changed that