Forum Discussion
Angel_Lopez_116
Altostratus
AltostratusHow is choosen the master or primary slot of the cluster?
Hi there,
I'd like to know how the cluster master slot is choosen? Is there any rule or algorithm to choose the primary slot on boot?
I'm wondering why my Viprion has decided this configuration after booting:
On the vCMP host:
-----------------------------------------
Sys::Cluster: default
-----------------------------------------
Address 192.168.16.32/21
Availability available
State enabled
Reason Cluster Enabled
Primary Slot ID 1
Primary Selection Time 11/27/14 09:03:31
----------------------------------------------------------------------------------------------------------------------
| Sys::Cluster Members
| ID Address Availability State Licensed HA Clusterd Reason
----------------------------------------------------------------------------------------------------------------------
| 1 192.168.16.33 available enabled true active running Run
| 2 192.168.16.34 available enabled true active running Run
| 3 :: unknown disabled false unknown shutdown Slot powered off or empty, manually disabled
| 4 :: unknown disabled false unknown shutdown Slot powered off or empty, manually disabled
On the guest:
-----------------------------------------
Sys::Cluster: default
-----------------------------------------
Address 192.168.16.55/21
Availability available
State enabled
Reason Cluster Enabled
Primary Slot ID 2
Primary Selection Time 11/27/14 09:06:27
----------------------------------------------------------------------------------
| Sys::Cluster Members
| ID Address Availability State Licensed HA Clusterd Reason
----------------------------------------------------------------------------------
| 1 :: available enabled true active running Run
| 2 :: available enabled true active running Run
| 3 :: unknown enabled false unknown shutdown Slot powered off or empty
| 4 :: unknown enabled false unknown shutdown Slot powered off or empty
I'd expect to see the guest active on slot 1 too, how is this?
It doesn't matter that the slot 1 is the active one for the host and slot 2 for the guest?
Brad_ParkerCirrus
It doesn't matter which blade is chosen as the primary for either the vCMP host or vCMP guest. If you had more blades and more guests its entirely possible to have the primary of all of them be different. As to how that decision is made, I have not found documentation on that, though through observations it appears it generally chooses the first available slot but don't quote me on that. It may choose the least busy, but I honestly couldn't say for sure.
Angel_Lopez_116So the primary role is just to set the source from which the system will be replicated to a new blade, right? It doesn't have any other relevance.- Brad_Parker"When the cluster initializes, one blade is determined to be the primary blade and all other blades are secondary blades. In addition to processing traffic like other blades, the primary blade is a management blade, which sets and maintains the configuration for the whole cluster." https://support.f5.com/kb/en-us/solutions/public/10000/700/sol10778.html?sr=29127145
Brad_Parker_139Nacreous
It doesn't matter which blade is chosen as the primary for either the vCMP host or vCMP guest. If you had more blades and more guests its entirely possible to have the primary of all of them be different. As to how that decision is made, I have not found documentation on that, though through observations it appears it generally chooses the first available slot but don't quote me on that. It may choose the least busy, but I honestly couldn't say for sure.
- Angel_Lopez_116So the primary role is just to set the source from which the system will be replicated to a new blade, right? It doesn't have any other relevance.
- Brad_Parker_139"When the cluster initializes, one blade is determined to be the primary blade and all other blades are secondary blades. In addition to processing traffic like other blades, the primary blade is a management blade, which sets and maintains the configuration for the whole cluster." https://support.f5.com/kb/en-us/solutions/public/10000/700/sol10778.html?sr=29127145
Nick_T_68319Nimbostratus
I'm not 100% sure, but I think it's whatever blade boots up faster and gets it's services running. On mine I noticed, if Slot1 is primary, then you reboot the chassis, the secondary blades reboot faster. So after the next reboot Slot2 will be primary.
- Angel_Lopez_116I see... it seems that there's no rule to decide who will be the master.