„WARNUNG:Verbindung zu lvmetad konnte nicht hergestellt werden. Fallback to Device Scanning“ – Fehler beim Ausführen von LVM-Befehlen

Das Problem

Die folgenden LVM-Befehle zeigen Fehler:

# pvs
WARNING: Failed to connect to lvmetad. Falling back to device scanning.    <<<
PV VG Fmt Attr PSize PFree
/dev/sd[X][partition_number] [vg_name] lvm2 a-- [size]g [available_free_space]g

# vgs
WARNING: Failed to connect to lvmetad. Falling back to device scanning.    <<<
VG #PV #LV #SN Attr VSize VFree
[vg_name] [number_of_pvs]  [number of lvs] 0 wz--n- [size]g [available_free_space]g

# lvs
WARNING: Failed to connect to lvmetad. Falling back to device scanning.    <<<
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
[lv_name] [vg_name] -wi-ao---- [size]g

Fehler aus /var/log/messages-Datei:

# grep lvmetad /var/log/messages
Sep 8 20:34:29 [hostname] systemd: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Unit is masked.
Sep 8 20:34:29 [hostname] lvm: WARNING: Failed to connect to lvmetad. Falling back to device scanning.
Sep 8 20:34:31 [hostname] lvm: WARNING: Failed to connect to lvmetad. Falling back to device scanning.
Sep 8 20:34:31 [hostname]t lvm: pvscan[642] activating all directly (lvmetad unused) 8:17
Sep 8 20:34:31 [hostname] lvm: WARNING: Autoactivation reading from disk instead of lvmetad.
Sep 8 20:34:31 [hostname] lvm: WARNING: Failed to connect to lvmetad. Falling back to device scanning.
Sep 8 20:34:31 [hostname] lvm: pvscan[644] activating all directly (lvmetad unused) 8:2
Sep 8 20:34:31 [hostname] lvm: WARNING: Autoactivation reading from disk instead of lvmetad.

Die Lösung

Der lvm2-lvmetad.service und lvm2-lvmetad.socket Dienste wurden deaktiviert, ohne dass die richtigen Schritte befolgt wurden. Die /etc/lvm/lvm.conf ist für die Verwendung von use_lvmetad konfiguriert, wobei die Dienste lvm2-lvmetad.service und lvm2-lvmetad.socket maskiert wurden.

# grep "use_lvmetad =" /etc/lvm/lvm.conf
use_lvmetad = 1

# systemctl status lvm2-lvmetad.service
● lvm2-lvmetad.service
Loaded: masked (/dev/null; bad)      >>>>> Masked      
Active: inactive (dead)
Warning: lvm2-lvmetad.service changed on disk. Run 'systemctl daemon-reload' to reload units.

# systemctl status lvm2-lvmetad.socket
● lvm2-lvmetad.socket
Loaded: masked (/dev/null; bad)      >>>>> Masked
Active: inactive (dead)

Sep 08 20:34:29  systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Unit is masked.
Sep 08 20:34:32  systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Invalid request descriptor
Sep 08 20:34:38  systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Unit is masked.
Sep 08 20:34:38  systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Unit is masked.
Warning: lvm2-lvmetad.socket changed on disk. Run 'systemctl daemon-reload' to reload units.

- Demaskieren Sie die lvm2-lvmetad.socket und lvm2-lvmetad.service Erste. Starten und aktivieren Sie dann die Dienste beim Booten mit den folgenden Befehlen.

# systemctl unmask lvm2-lvmetad.service lvm2-lvmetad.socket
# systemctl start lvm2-lvmetad.service lvm2-lvmetad.socket
# systemctl enable lvm2-lvmetad.service lvm2-lvmetad.socket

Wenn lvm2-lvmetad.socket und lvm2-lvmetad.service deaktiviert werden müssen, muss /etc/lvm/lvm.conf so konfiguriert werden, dass "use_lvmetad" nicht verwendet wird. (d.h. use_lvmetad =0)