[PVE-User] Changing votes and quorum

[Dewangga Alam]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

Hello!

Thanks for your response, Thomas.

On 29/10/18 16.14, Thomas Lamprecht wrote:
> Hi!
> 
> Am 10/28/2018 um 02:54 PM schrieb Dewangga Alam: Hello!
> 
> I was new in proxmox and am trying to build large scale proxmox
> 5.2 cluster (>128 nodes). My `/etc/pve/corosync.conf` configuration
> like :
> 
> ``` nodelist { node { name: node1 nodeid: 1 quorum_votes: 1 
> ring0_addr: 192.168.24.2 } ... skip till nodes 28 ... node { name:
> node28 nodeid: 28 quorum_votes: 1 ring0_addr: 192.168.24.110 } } 
> quorum { provider: corosync_votequorum expected_votes: 16
> 
>> expected_votes must be your real highest expected votes.

[..]

> 
> last_man_standing: 1 last_man_standing_window: 20000
> 
> 
> 
> } totem { cluster_name: px-cluster1 config_version: 90 window_size:
> 300 interface { ringnumber: 0 } ip_version: ipv4 secauth: on 
> transport: udpu version: 2 } ```
> 
> My cluster have 28 nodes in each rack. and total nodes will 28
> nodes*5 racks. So it will 140 nodes in a cluster. From the
> adjustment above, I wonder there's affected to pve/corosync.conf
> configuration, but in fact, it didn't.
> 
> So my basic question, when I invoke `pvecm status` in a node, the 
> result wasn't as I expect. Then, is it possible to change
> votequorum configuration?
> 
>> What wasn't as expected? That your set expected_votes is not 
>> "accepted" by corosync? That is expected behaviour.
> 
>> What is the real problem you want to solve?

I want to build > 32 nodes in one cluster, and I am expect that
expected_votes can be controlled lower than real votes. I thought, it
should be make a quorum if the 50%+1 formulas aren't met.

Is it a best practice?

> 
> 
> 
> ``` Quorum information ------------------ Date:             Sun Oct
> 28 20:51:42 2018 Quorum provider:  corosync_votequorum Nodes:
> 28 Node ID:          0x00000002 Ring ID:          1/27668 Quorate:
> Yes
> 
> Votequorum information ---------------------- Expected votes:   28
> 
>> if more nodes are online than you set expected it will
>> automatically use the real node count, i.e. formula would be
> 
>> expected = max(user_set_expected, #nodes_quorate_online)

So, if real nodes online are 56, then I set expected_votes: 16. it
will be override by real nodes online, right? I expect, that if first
16 nodes visible at the first time, it will be quorate as soon as
possible.

> 
>> Note that last_man_standing is not really recommended by us, if
>> you employ it nonetheless then please test it carefully before
>> rolling out in production, maybe take also a look at wait_for_all
>> flag to take this a bit on the save side for cluster cold boots.
> 
> Highest expected: 28 Total votes:      28 Quorum:           15 
> Flags:            Quorate LastManStanding ```
> 
> 
-----BEGIN PGP SIGNATURE-----

iQIzBAEBCAAdFiEEZpxiw/Jg6pEte5xQ5X/SIKAozXAFAlvXNxcACgkQ5X/SIKAo
zXD/kxAArh0Cs67F7D2ZciTpCEU4XjeA5fntB97mril7SerjkFgYTdCGNOCZjQxS
3u7lioZmtrSXak+SZx6hPwptssyFde+OmfnL4R6NHLAs6Lx9FQyj8sG8O2+6VJmz
YjzkamHtLox7rjUMtWB2RXf15fAlVRLnhshIxrjnkNdJ2YhkbDUoREmq1s27aqCI
ASqD2KlawInEMenADEiGRtuRGe05O77DwyP7wSJuT1DTxOB1Zxk1asixjeOvCle7
5BsAzaCL/5VoLGWx98ezjMBIXngk1TVE5tFFlEVQSXWqOG3y0JZfy6nhl4a+zF/b
eCVvU14XWsZPI8d/57En+PV19rmGpthnc4oNxKDWMGm7ce6pY1m3koZuVnxP0Ugv
H3ZzptUR2MfY+vvfax50oor6eFGQPTNKljDUlZa0xYpqrAsdrBDo1uJTjGFEQzkV
5yLRSQYyskHknJJFMvIU+Sey9wj8yeLcNRZOsWQL3D15pvpr4oShWQIpJE3F8gE9
doUJ4w+I0iM9Av91ECrlgZEjAHaSeo+WxwN6NJoIvXXOJKE2OOU3RMXFabgdFoeS
LXAvGks9aaefdwaiCiwT2bfB3FJkqKZEz98s1T9CJ5tDNpo4r5afA4kATQ4NJ95L
29JMd7Z0Hio24y5oLbGpNmDx0R8+YjahBsd7n+QwzFTjk+3ATKI=
=fcym
-----END PGP SIGNATURE-----