Not to ruffle feathers Val, but I never seen in normal circumstances cluster member entering READY state apart from upgrade when members are running different versions (HW and/or SW). As far as I have seen it it does DOWN > INIT > STANDBY (or ACTIVE if it's a higher priority member with corresponding cluster setting)
There is a fairly set list of cases that will trigger READY state on VSX: (sk42096 )
There are cluster members with a lower software version on this subnet / VLAN
[member with higher software version will go into state 'Ready'].
The number of CoreXL FireWall instances on cluster members is different
[member with greater number of CoreXL FW instances will go into state 'Ready'].
Note: This applies only to R80.10 and lower versions.
The ID numbers of CoreXL FireWall instances and handling CPU core numbers on cluster members are different.
On Gaia OS - Linux kernels on cluster members are different (32-bit vs 64-bit)
[member with higher kernel edition will go into state 'Ready'].
On Gaia OS - Cluster member runs in VSX mode, while other members run in Gateway mode
[member in VSX mode will go into state 'Ready'].
Also checked fwk.elg history on my VSX and did not see a single READY state there apart from upgrade 🙂
grep CLUS $FWDIR/log/fwk.elg* | grep "State change"|grep READY
[3 Jul 17:09:11][fw4_0];[vs_0];CLUS-115303-1: State change: DOWN -> READY | Reason: Member with older software release has been detected
[3 Jul 17:15:54][fw4_0];[vs_0];CLUS-115303-1: State change: INIT -> READY | Reason: Member with older software release has been detected
[3 Jul 17:36:37][fw4_0];[vs_0];CLUS-115303-1: State change: INIT -> READY | Reason: Member with older software release has been detected
[3 Jul 17:55:28][fw4_0];[vs_0];CLUS-112100-1: State change: READY -> DOWN | Reason: FULLSYNC PNOTE
@Vincent_Croes - I hope you have verified CoreXL allocations on both members and they are identical and also looked at fwk.elg logs, they might give a hint for member entering READY state?