Ceph

Configuration:
1 mon and 1 osd node, number of OSD's 7

Steps followed:

1. Make Cluster up in single node and ensure Cluster state is "OK"
2. do purge and uninstall ceph on OSD node
3. After uninstallation OSD node status

:~$ sudo ceph -s
sudo: ceph: command not found

:~$ sudo ceph -v
sudo: ceph: command not found

:~$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 55.4G 0 disk
??sda1 8:1 0 9.3G 0 part /
??sda2 8:2 0 1K 0 part
??sda5 8:5 0 1.9G 0 part [SWAP]
??sda6 8:6 0 44.2G 0 part /home
sdb 8:16 0 372.6G 0 disk
??sdb1 8:17 0 367.6G 0 part
??sdb2 8:18 0 5G 0 part
sdc 8:32 0 372.6G 0 disk
??sdc1 8:33 0 367.6G 0 part
??sdc2 8:34 0 5G 0 part
sdd 8:48 0 372.6G 0 disk
??sdd1 8:49 0 367.6G 0 part
??sdd2 8:50 0 5G 0 part
sde 8:64 0 372.6G 0 disk
??sde1 8:65 0 367.6G 0 part
??sde2 8:66 0 5G 0 part
sdf 8:80 0 372.6G 0 disk
sdg 8:96 0 372.6G 0 disk
sdh 8:112 0 372.6G 0 disk
sdi 8:128 0 372.6G 0 disk
??sdi1 8:129 0 367.6G 0 part
??sdi2 8:130 0 5G 0 part
sdj 8:144 0 372.6G 0 disk
??sdj1 8:145 0 367.6G 0 part
??sdj2 8:146 0 5G 0 part
sdk 8:160 0 372.6G 0 disk
??sdk1 8:161 0 367.6G 0 part
??sdk2 8:162 0 5G 0 part
sdl 8:176 0 372.6G 0 disk
??sdl1 8:177 0 367.6G 0 part
??sdl2 8:178 0 5G 0 part
sdm 8:192 0 372.6G 0 disk
sdn 8:208 0 745.2G 0 disk
sr0 11:0 1 1024M 0 rom

4. MON node status
:~$ sudo ceph -s
cluster 443ad6db-f0f0-44d5-b44c-36f86d29abee
health HEALTH_WARN 1391 pgs stale; 1391 pgs stuck stale
monmap e1: 1 mons at

{rack1-2=0.0.0.0:6789/0}
, election epoch 1, quorum 0 rack1-2
osdmap e1592: 7 osds: 2 up, 2 in
pgmap v63658: 1878 pgs, 7 pools, 389 GB data, 99717 objects
318 GB used, 416 GB / 734 GB avail
1391 stale+active+clean
487 active+clean

:~$ sudo ceph osd tree

1.id weight type name up/down reweight
-1 2.54 root default
-2 2.54 host rack1-1
0 0.38 osd.0 down 0
1 0.36 osd.1 down 0
2 0.36 osd.2 up 1
4 0.36 osd.4 down 0
6 0.36 osd.6 down 0
3 0.36 osd.3 up 1
5 0.36 osd.5 down 0

:~$ sudo ceph osd stat
osdmap e1592: 7 osds: 2 up, 2 in

:~$ sudo ceph pg stat
v63658: 1878 pgs: 1391 stale+active+clean, 487 active+clean; 389 GB data, 318 GB used, 416 GB / 734 GB avail

:~$ sudo ceph mon stat
e1: 1 mons at {rack1-2=0.0.0.0:6789/0}
, election epoch 1, quorum 0 rack1-2

Still mon node shows 2 OSD's are up, but there is no OSD mount present in OSD node and observed cluster in same state after 2 days.
Tried running IO, IO's not proceded.
There is no OSD or other logs since ceph is uninstalled.