FastDFS Tracker端配置文件详解及启动注意事项

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# is this config file disabled
# false for enabled
# true for disabled
disabled=false
#当前配置是否不可用false可用，true不可用

# bind an address of this host
# empty for bind all addresses of this host
bind_addr=
#是否绑定IP如果一个服务器上有多个IP则设置哪个IP可用，如果不设置则不限制

# the tracker server port
port=22122
#端口

# connect timeout in seconds
# default value is 30s
connect_timeout=30
#针对socket套接字函数connect的连接超时时间设置

# network timeout in seconds
# default value is 30s
network_timeout=60
#设置网络超时，单位秒，发送或接收数据时，如果在超时时间之后依然不能进行，则本次网络通讯失败

# the base path to store data and log files
base_path=/home/fdfs
#配置保存根目录地址，这个目录必须存在，子目录将自动创建

# max concurrent connections this server supported
max_connections=256
#最大连接数

# work thread count, should <= max_connections
# default value is 4
# since V2.00

work_threads=1
#工作线程数，通常设置为CPU数量

# the method of selecting group to upload files
# 0: round robin
# 1: specify group
# 2: load balance, select the max free space group to upload file
store_lookup=2
#上传组（卷）的方式：0轮询，1：指定，2：负载平衡（剩余空间最大选择）

# which group to upload file
# when store_lookup set to 1, must set store_group to the group name
store_group=group2
#如果上一参数选择1方式，即制定祖名，当前参数用来设置指定的组，如果选择其他方式，当前参数无效

# which storage server to upload file
# 0: round robin (default)
# 1: the first server order by ip address
# 2: the first server order by priority (the minimal)
store_server=0
#同组推送方式0.轮询方式，1.根据ip地址进行排序选择第一个服务器，2.根据优先级进行排序（优先级由storeServer的配置文件中upload_priority属性设置）

# which path(means disk or mount point) of the storage server to upload file
# 0: round robin
# 2: load balance, select the max free space path to upload file

store_path=0
#选择哪个文件目录进行上传（一个StroeServer上面可以有多个base_path）0.轮询，2.剩余空间最大

# which storage server to download file
# 0: round robin (default)
# 1: the source storage server which the current file uploaded to
download_server=0
#选择哪个storeServer最为下载服务器，0.轮询，1.哪个为源则哪个下载

# reserved storage space for system or other applications.
# if the free(available) space of any stoarge server in 
# a group <= reserved_storage_space, 
# no file can be uploaded to this group.
# bytes unit can be one of follows:
### G or g for gigabyte(GB)
### M or m for megabyte(MB)
### K or k for kilobyte(KB)
### no unit for byte(B)
### XX.XX% as ratio such as reserved_storage_space = 10%
reserved_storage_space = 10%
#系统保留空间大小，用来保证系统和其他应用的正常运行

#standard log level as syslog, case insensitive, value list:
### emerg for emergency
### alert
### crit for critical
### error
### warn for warning
### notice
### info
### debug
log_level=info
#日志级别

#unix group name to run this program, 
#not set (empty) means run by the group of current user

run_by_group=
#使用那个系统用户组运行FastDFS，默认为启动线程的用户组

#unix username to run this program,
#not set (empty) means run by current user
run_by_user=
#使用那个系统用户运行FastDFS。默认为启动线程的用户

# allow_hosts can ocur more than once, host can be hostname or ip address,
# "*" means match all ip addresses, can use range like this: 10.0.1.[1-15,20] or
# host[01-08,20-25].domain.com, for example:
# allow_hosts=10.0.1.[1-15,20]
# allow_hosts=host[01-08,20-25].domain.com
allow_hosts=*
#设置可以连接当前tracker的IP范围，包括client和store_server

# sync log buff to disk every interval seconds
# default value is 10 seconds
sync_log_buff_interval = 10
#同步或刷新日志到本地硬盘的时间间隔，单位：秒

# check storage server alive interval seconds
check_active_interval = 120
#检测storage_server的存活状态时间间隔，单位：秒，本参数要大于storage server的心跳包发送间隔一般为2-3倍

# thread stack size, should >= 64KB
# default value is 64KB
thread_stack_size = 64KB
#tracker server的线程栈大小，要求大于等于64K

# auto adjust when the ip address of the storage server changed
# default value is true
storage_ip_changed_auto_adjust = true
#当storage server的IP发生变化时集群是否自动调整。只有在storage server进程重启时才能完成自动调整

# storage sync file max delay seconds
# default value is 86400 seconds (one day)
# since V2.00
storage_sync_file_max_delay = 86400
#存储服务器之间同步文件的最大延迟时间，缺省为1天，可以根据实际情况进行调整

# the max time of storage sync a file
# default value is 300 seconds
# since V2.00
storage_sync_file_max_time = 300
#同步一个文件需要消耗的最大时间，缺省为300秒，即5分钟

# if use a trunk file to store several small files
# default value is false
# since V3.00
use_trunk_file = false 
#是否使用小文件合并存储特性，缺省关闭，打开时可以减少碎片文件的出现，但同时加大服务器的负载

# the min slot size, should <= 4KB
# default value is 256 bytes
# since V3.00
slot_min_size = 256
#为trunk file分配的最小字节数，比如一个文件只有16字节，根据当前设置，也会为其分配256字节

# the max slot size, should > slot_min_size
# store the upload file to trunk file when it's size <=  this value
# default value is 16MB
# since V3.00
slot_max_size = 16MB
#为trunk file分配的最大字节数，如果文件小于大小则使用trunk方式存储，当文件大小大于这个数值是直接保存到一个文件中（不采用合并存储方式）

# the trunk file size, should >= 4MB
# default value is 64MB
# since V3.00
trunk_file_size = 64MB
#trunk file的大小，不建议设置过大

# if create trunk file advancely
# default value is false
# since V3.06
trunk_create_file_advance = false
#是否提前创建好trunk文件，只用当这个参数设置为true时下面的3个以trunk_create_file开头的参数将不用设置

# the time base to create trunk file
# the time format: HH:MM
# default value is 02:00
# since V3.06
trunk_create_file_time_base = 02:00
#创建trunk file的起始时间点，当前为凌晨2点开始

# the interval of create trunk file, unit: second
# default value is 38400 (one day)
# since V3.06
trunk_create_file_interval = 86400
#提前创建trunk file的时间间隔，默认为1天

# the threshold to create trunk file
# when the free trunk file size less than the threshold, will create 
# the trunk files
# default value is 0
# since V3.06
trunk_create_file_space_threshold = 20G
#提前创建trunk file时，需要达到的空闲trunk大小
#例如：当前配置为20G，现在空闲的trunk file大小为4G，那么只创建16G的trunk file

# if check trunk space occupying when loading trunk free spaces
# the occupied spaces will be ignored
# default value is false
# since V3.09
# NOTICE: set this parameter to true will slow the loading of trunk spaces 
# when startup. you should set this parameter to true when neccessary.
trunk_init_check_occupying = false
#trunk file 初始化时，是否检查可用空间是否被占用

# if ignore storage_trunk.dat, reload from trunk binlog
# default value is false
# since V3.10
# set to true once for version upgrade when your version less than V3.10
trunk_init_reload_from_binlog = false
#是否无条件从trunk binlog中加载trunk可用空间信息

# if use storage ID instead of IP address
# default value is false
# since V4.00
use_storage_id = false
#是否使用 serverID作为storage server标识

# specify storage ids filename, can use relative or absolute path
# since V4.00
storage_ids_filename = storage_ids.conf
#use_storage_id设置为true，才需要设置本参数，详见源码目录下的conf/storage_ids.conf
#这个文件中设置组名、serverID和对应的IP地址

# id type of the storage server in the filename, values are:
## ip: the ip address of the storage server
## id: the server id of the storage server
# this paramter is valid only when use_storage_id set to true
# default value is ip
# since V4.03
id_type_in_filename = ip
#use_storage_id设置为true时才需要设置本参数


# if store slave file use symbol link
# default value is false
# since V4.01
store_slave_file_use_link = false
#存储从文件是否采用symbol link（符号链接）方式
#如果设置为true，一个从文件将占用两个文件：原始文件及指向它的符号链接

# if rotate the error log every day
# default value is false
# since V4.02
rotate_error_log = false
#是否定期轮转error log，目前仅支持一天轮转一次

# rotate error log time base, time format: Hour:Minute
# Hour from 0 to 23, Minute from 0 to 59
# default value is 00:00
# since V4.02
error_log_rotate_time=00:00
#error log定期轮转的时间节点，rotate_error_log参数设置为true时，本参数有效

# rotate error log when the log file exceeds this size
# 0 means never rotates log file by log file size
# default value is 0
# since V4.02
rotate_error_log_size = 0
#error log按大小进行轮转 0代表不按大小进行轮转，否则当error log文件达到大小则轮转

# if use connection pool
# default value is false
# since V4.05
use_connection_pool = false
#是否使用连接池

# connections whose the idle time exceeds this time will be closed
# unit: second
# default value is 3600
# since V4.05
connection_pool_max_idle_time = 3600
#连接池链接的最大生存时间，单位秒，use_connection_pool设置为true时有效

# HTTP port on this tracker server
http.server_port=8080
#http服务端口，默认情况下V4.06是不安装http服务的，详见INSTALL文件


# check storage HTTP server alive interval seconds
# <= 0 for never check
# default value is 30
http.check_alive_interval=30
#检查长链接的存活时间30秒

# check storage HTTP server alive type, values are:
#   tcp : connect to the storge server with HTTP port only, 
#        do not request and get response
#   http: storage check alive url must return http status 200
# default value is tcp
http.check_alive_type=tcp
#长链接的存在方式，当前配置为tcp方式

# check storage HTTP server alive uri/url
# NOTE: storage embed HTTP server support uri: /status.html
http.check_alive_uri=/status.html
#利用什么标识进行检查

附件中有保存好的traker.conf文件，需要的可以进行下载 
配置完成之后，运行 

/usr/local/bin/fdfs_trackerd /etc/fdfs/tracker.conf

tracker端就可以运行成功了。 
可能出现的问题有两个 
1.base_path设置的目录不存在，如果报这个错误，需要按base_path的设置创建一个目录 
2.找不到libevent-2.0.so.5 
如果找不到这个，请确认安装时的安装位置 
一般这个库会安装到/usr/local/lib中 
而我们的fdfs_trackerd会到/usr/lib中去查找，所以使用 

ln -s /usr/local/lib/libevent-2.0.so.5 /usr/lib/libevent-2.0.so.5

将库加载到/usr/lib中就可以了