upgarding 2 nodes to corosync3

Kevin Myers

New Member
Jul 14, 2017
18
0
1
43
Hi,

Im having a peculiar issue.

My nodes used infiniband in connected mode for cluster network, and storage (different interfaces) .

The cluster network runs on a 10.1,100.x range, and the ipoib device looks like
ib1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 65520
inet 10.1.100.2 netmask 255.255.255.0 broadcast 10.1.100.255

the other node is 10.1.100.1 with the same mtu.

in the corrosync config I have

nodelist {
node {
name: kvm1
nodeid: 1
quorum_votes: 1
ring0_addr: 10.1.100.1
}
node {
name: kvm2
nodeid: 2
quorum_votes: 1
ring0_addr: 10.1.100.2
}

and

interface {
bindnetaddr: 10.1.100.1
ringnumber: 0
}


Now the problem is pvecm status shows only the local node on each of the nodes, and spamming to the syslog on both nodes I see :



Jul 29 11:16:10 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:10 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:10 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:10 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:10 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:11 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 11:16:12 kvm2 corosync[4025739]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.


This setup worked perfectly on corrosync2.

Do you think the MTU of 65520 is in some way not compatible with corosync3 ? or is there any other gems anyone could suggest ??

All the best
Kevin M
 

Kevin Myers

New Member
Jul 14, 2017
18
0
1
43
I had tried earlier fiddling with netmtu, but decided to try setting some different values, (1500, 20000 , 65520) , all of which make nod difference we end up with

Jul 29 14:40:14 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:14 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:14 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:14 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:15 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.
Jul 29 14:40:16 kvm1 corosync[4039025]: [KNET ] pmtud: Aborting PMTUD process: Too many attempts. MTU might have changed during discovery.

spamming the logs

ive created an issue with at https://github.com/kronosnet/kronosnet/issues/241 as this does seem to be a bug in my opinion when looking at the code https://github.com/kronosnet/kronosnet/blob/master/libknet/threads_pmtud.c

best regards
Kevin M
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
3,462
540
113
the kronosnet devs already found two bugs (one in knet, one in the kernel) with your specific setup. as a quick workaround, lowering the MTU on the actual interface to something lower than 65484 should allow pmtud to work correctly. once there is a fix on the code side, we'll integrate it into our kronosnet packages and you should be able to bump the MTU again.
 
  • Like
Reactions: alchemycs

Kevin Myers

New Member
Jul 14, 2017
18
0
1
43
Hi Fabian,

It seems a patch have been applied to fix this, could it be integrated :)

Best regards
Kev
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
3,462
540
113
we are in close contact with upstream, once the fix is finalized both we and upstream will release fixed packages ASAP
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
3,462
540
113
you are probably following the upstream issue anyway, but packages with the proposed fix from upstream included are available on pvetest:
Code:
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libknet-dev_1.10-pve2_amd64.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libknet-doc_1.10-pve2_all.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libknet1-dbgsym_1.10-pve2_amd64.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libknet1_1.10-pve2_amd64.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libnozzle-dev_1.10-pve2_amd64.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libnozzle1-dbgsym_1.10-pve2_amd64.deb
http://download.proxmox.com/debian/pve/dists/buster/pvetest/binary-amd64/libnozzle1_1.10-pve2_amd64.deb
(corosync needs to be restarted for the fixed packages to be used)
 

Kevin Myers

New Member
Jul 14, 2017
18
0
1
43
Hi Fabian,

The patches did fix the MTU issue, however another ugly issue has raised its head .

I have a cluster of around 30 nodes, ( I know all the warnings of corosync2 and 16 nodes however this worked awesomely on corrosync2) .

I started to move nodes from CS2 to CS3 in prep of the 5-6 move, and all seemed good to start with,, after node 5 convergence started slowing down, when I got to node 17 the node didnt join ring 0 and created a new ring 20, (problem 1) at this point CS3 on the previous 16 nodes was consuming 200-400% cpu on the hardware nodes (problem 2)

Not sure the best path to report these issue, you do seem to have 'contacts' , any advise is appreciated.

best regards
Kev
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
3,462
540
113
Hi Fabian,

The patches did fix the MTU issue, however another ugly issue has raised its head .

I have a cluster of around 30 nodes, ( I know all the warnings of corosync2 and 16 nodes however this worked awesomely on corrosync2) .

I started to move nodes from CS2 to CS3 in prep of the 5-6 move, and all seemed good to start with,, after node 5 convergence started slowing down, when I got to node 17 the node didnt join ring 0 and created a new ring 20, (problem 1) at this point CS3 on the previous 16 nodes was consuming 200-400% cpu on the hardware nodes (problem 2)

Not sure the best path to report these issue, you do seem to have 'contacts' , any advise is appreciated.

best regards
Kev
could you provide the corosync.conf and network setup, and describe how you did the upgrade?

what do you mean with "didn't join ring0 and created a new ring 20" ?

as always, logs would also be great, at least of pve-cluster and corosync services..

edit: and was this upgrade done with the patched libknet, or the regular one from the corosync-3 repo?
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE and Proxmox Mail Gateway. We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get your own in 60 seconds.

Buy now!