cubefs/docs/source/user-guide/file.md

Using File Storage

Environment Dependencies

• Insert the kernel FUSE module
• Install libfuse

modprobe fuse
yum install -y fuse

Mounting the File System

After successfully creating a replica volume, mount the volume by executing the following command:

cfs-client -c client.json

After successful execution, you can use the df -h command to view the mount point. If the execution fails, you can judge according to the content of output.log in the log directory.

The example configuration file is as follows:

{
    "mountPoint":"/mnt/cfs",
    "subdir":"/",
    "volName":"vol_test",
    "owner":"test",
    "accessKey":"**********",
    "secretKey":"*********",
    "masterAddr":"192.168.0.1:17010",
    "rdonly":"false",
    "logDir":"/home/service/var/logs/cfs/log",
    "logLevel":"warn",
    "profPort":"17410"
}

The meaning of each parameter in the configuration file is shown in the following table:

Parameter	Type	Meaning	Required
mountPoint	string	Mount point	Yes
subdir	string	Mount subdirectory	No
volName	string slice	Volume name	Yes
owner	string	Volume owner	Yes
accessKey	string	Authentication key of the user to which the volume belongs	Yes
secretKey	string	Authentication key of the user to which the volume belongs	Yes
masterAddr	string	Master node address	Yes
rdonly	bool	Mount as read-only, default is false	No
logDir	string	Log storage path	No
logLevel	string	Log level: debug, info, warn, error	No
profPort	string	Golang pprof debugging port	No

Other configuration parameters can be set according to actual needs:

Parameter	Type	Meaning	Required
exporterPort	string	Port for Prometheus to obtain monitoring data	No
consulAddr	string	Monitoring registration server address	No
lookupValid	string	Validity period of kernel FUSE lookup, in seconds	No
attrValid	string	Validity period of kernel FUSE attribute, in seconds	No
icacheTimeout	string	Validity period of client inode cache, in seconds	No
enSyncWrite	string	Enable DirectIO synchronous write, that is, DirectIO forces data nodes to write to disk	No
autoInvalData	string	Use the AutoInvalData option for FUSE mounting	No
writecache	bool	Use the write cache function of the kernel FUSE module. This function requires the kernel FUSE module to support write cache. The default is false.	No
keepcache	bool	Keep the kernel page cache. This function requires the writecache option to be enabled. The default is false.	No
token	string	If enableToken is enabled when creating a volume, fill in the token corresponding to the permission.	No
readRate	int	Limit the number of reads per second. The default is unlimited.	No
writeRate	int	Limit the number of writes per second. The default is unlimited.	No
followerRead	bool	Read data from the follower. The default is false.	No
disableDcache	bool	Disable Dentry cache. The default is false.	No
fsyncOnClose	bool	Perform fsync operation after the file is closed. The default is true.	No
maxcpus	int	The maximum number of CPUs that can be used, which can limit the CPU usage of the client process.	No
enableXattr	bool	Whether to use xattr. The default is false.	No
enableBcache	bool	Whether to enable local level 1 cache. The default is false.	No
maxStreamerLimit	string	When local level 1 cache is enabled, the number of file metadata caches.	No
bcacheDir	string	The target directory for read cache when local level 1 cache is enabled.	No

Unmounting the File System

Execute the following command to unmount the replica volume:

umount -l /path/to/mountPoint

/path/to/mountPoint is the mount path in the client configuration file.

Live Upgrade or hot restart

cfs-client -c fuse.json -r -p 27510

Before live-upgrading, old cfs-client is running with profPort 27510. -r restore FUSE instead of mounting. -p 27510 tells new cfs-client to communicate with old cfs-client through port 27510.

Enabling Level 1 Cache

The local read cache service deployed on the user client is not recommended for scenarios where the data set has modified writes and requires strong consistency. After deploying the cache, the client needs to add the following mount parameters, and the cache will take effect after remounting.

./cfs-bcache -c bcache.json

The meaning of each parameter in the configuration file is shown in the following table:

{
   "cacheDir":"/home/service/var:1099511627776",
   "logDir":"/home/service/var/logs/cachelog",
   "logLevel":"warn"
}

Parameter	Type	Meaning	Required
cacheDir	string	Local storage path for cached data: allocated space (Byte)	Yes
logDir	string	Log path	Yes
logLevel	string	Log level	Yes