Dell Unity：租期到期后 NAS 服务器仍持有 NFSv4 锁定超过 5 分钟

• 客户端非正常关闭后，可能会在 Unity NAS 服务器上观察到受影响文件上的 NFS 锁定长达六分钟。
• 在 Unity 释放锁定之前，其他客户端无法锁定文件。 
• 这些锁定使用 svc_lockd 命令。

root@none spa:/cores/service/user# date ;svc_lockd NAS_Server list
Mon Oct 27 08:43:36 UTC 2025
NAS_Server : commands processed: 1
command(s) succeeded
output is complete

FileSystem: ufs64 rw /.etc SV20000009=536870921 expfsidstr=67fcca47-e0ae-3301-b819-0e0e84d61219  nooplock triggerlevel=0 nocepp nfsv4locking=ADVISORY renamepolicy=CIFS accesspolicy=NATIVE minactfssize=2816  NumTimesFsckHasModifiedFS=0
  inum=9465
    fldp=0x0008c74ba8 Deleg=0 Opens=1 RangeLocks: Mandatory=0 Advisory=0
  inum=9466
    fldp=0x0008c74d00 Deleg=0 Opens=1 RangeLocks: Mandatory=0 Advisory=0
  inum=9468
    fldp=0x0008c75260 Deleg=0 Opens=1 RangeLocks: Mandatory=0 Advisory=0

FileSystem: ufs64 rw /Ghost_NFS01_Official_FS SV2000000a=536870922 expfsidstr=67fccdbd-4304-dbdd-3b8f-00601696feeb  nooplock triggerlevel=512 nocepp nfsv4locking=MANDATORY renamepolicy=CIFS accesspolicy=UNIX minactfssize=2816 thinprovisioning maxsize=204544 hwm=0  NumTimesFsckHasModifiedFS=0
  inum=9465
    fldp=0x0008c753b8 Deleg=0 Opens=1 RangeLocks: Mandatory=1 Advisory=0   <<<<<<<<<<< Lock placed by client on file inode 9465

Command succeeded

root@none spa:/cores/service/user# date ;svc_lockd NAS_Server info fldp=0x0008c753b8
Mon Oct 27 08:43:46 UTC 2025
NAS_Server : commands processed: 1
command(s) succeeded
output is complete

fldp=0x0008c753b8 inum=9465 ref=1 delegp=0x0000000000 totalLocksCount=2 layoutsCount=0
 Global accessMode=[RWd], denyMode=[rwd]
 Open access=RD-WR deny=NONE [NFSv4_Linux NFSv4.2 test_client_OPEN_0x0008577fc8]

 Lock 0x00064-00064:     -SHR-MAND [credp=0x000857dfc8 NFSv4_Linux NFSv4.2 test_client_LOCK_0x000857dfc8]  <<<<<<<<<< byte-range shared mandatory lock

NFSv4 协议使用租用期，在此期间，服务器向客户端授予文件锁定。客户端必须定期续订此租约以保持锁定。 

• 如果客户端意外关闭，则无法续订租约。
• Unity NAS 服务器等待租约到期，然后再尝试收回锁定。
• 默认情况下，Unity 不会立即释放这些资源。一个隐藏参数， nfsv4.cleaningInterval，定义一个额外的等待期。
• 默认 nfsv4.cleaningInterval 值为 300 秒（5 分钟）。
• 因此，锁定的文件仅在标准租用期加上 5 分钟的清理间隔后才会释放，导致总等待时间约为 5 到 6 分钟。 

而 nfsv4.cleaningInterval 可以降低值以减少 NAS 服务器持有锁定的时间。

• 确认当前值 nfsv4.cleaningInterval 是。

root@none spa:/cores/service/user# svc_nas NAS_Server -param -facility nfsv4 -i cleaningInterval -v

NAS_Server :
param nfsv4.cleaningInterval added into the list of visible params

name                    = cleaningInterval
facility_name           = nfsv4
default_value           = 300
current_value           = 300
configured_value        =
param_type              = global
user_action             = none
change_effective        = immediate
range                   = (30,3600)
description             = Time interval in seconds between two successive clean up of orphan states

detailed_description
This param defines how long the server will keep client resources once the client has expired its lease. It is expressed in a count of seconds.

• 修改 nfsv4.cleaningInterval 参数设置为较低的值，例如 30 秒。 

root@none spa:/cores/service/user# svc_nas ALL -param -facility nfsv4 -modify cleaningInterval -v 30
 
SPA : done
SPB : done

• 确认该值设置为 30 秒。 

root@none spa:/cores/service/user# svc_nas NAS_Server -param -facility nfsv4 -i cleaningInterval -v
 
NAS_Server :
param nfsv4.cleaningInterval added into the list of visible params
 
name                    = cleaningInterval
facility_name           = nfsv4
default_value           = 300
current_value           = 30
configured_value        = 30
param_type              = global
user_action             = none
change_effective        = immediate
range                   = (30,3600)
description             = Time interval in seconds between two successive clean up of orphan states
 
detailed_description
This param defines how long the server will keep client resources once the client has expired its lease. It is expressed in a count of seconds.