connect Debian to Proxmox CEPH cluster and mount Cephfs

on client create the destination directory

mkdir -p /etc/pve/priv/

copy the keyring on the debian client: (uses admin keyring !!)

scp <proxmox_ip>:/etc/pve/priv/ceph.client.admin.keyring /etc/pve/priv/.

copy the configuration file :

scp <proxmox_ip>:/etc/pve/ceph.conf /etc/ceph/.

test

ceph status

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mount Cephfs on debian

1. on ceph:


generate a keyfile for client foo on proxmox:

ceph auth get-or-create client.foo \

    mds 'allow rw path=/ceph/mount/point' \

    mon 'allow r' \

    osd 'allow rw pool=cephfs_data' \

    -o /etc/pve/priv/ceph.client.foo.keyring

check the client with :
ceph auth list

generate a minimal config :
ceph config generate-minimal-conf

and copy the output in /etc/ceph/ceph.conf on the client

2. on client:

aptitude install libcephfs2 ceph-common ceph-fuse 

copy the keyring file from the client

mkdir -p /local/mount/point

add an entry in /etc/fstab like :

id=foo,conf=/etc/ceph/ceph.conf,client_mountpoint=/ceph/mount/point /local/mount/point fuse.ceph _netdev,defaults 0 0

_netdev here is important, otherwhise it does not boot 

3. then mount it 

sudo mount -a 

migrating from XCP-ng (xen) to Proxmox (LVM)

create the VM, be the closest to the XCP-ng VM on Proxmox
detach the disk

export the VM with Xencenter in ova/ovf format (GUI)

extract the ova : 

tar -xvf <ova_file.ova>
this result in a vhd + ovf file

convert the filedisk format:

qemu-img convert -f vpc <disk_file.vhd> -O qcow2 <disk_filename.qcow2>

import the disk to the vm :  

qm importdisk <vm_id> <disk_filename.qcow2> <storage> -format qcow2

attach the disk to the vm, then boot