LSOF commands
LSOF is the short form of "LiSt Open Files".
It is a command line utility which is used to list the information about the files that are opened by various processes.
In unix, everything is considered as a file, ( pipes, sockets, directories, devices, etc.).
So by using lsof, you can get the information about any opened files.
1). List all open files:
This command will provide list of open files of all active processes.
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lsof
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By default One file per line is displayed. Most of the columns are self explanatory. We will explain the details about couple of cryptic columns (FD and TYPE).
FD – Represents the file descriptor. Some of the values of FDs are,
cwd – Current Working Directory
txt – Text file
mem – Memory mapped file
mmap – Memory mapped device
NUMBER – Represent the actual file descriptor. The character after the number i.e ‘1u’, represents the mode in which the file is opened. r for read, w for write, u for read and write.
TYPE – Specifies the type of the file. Some of the values of TYPEs are,
REG – Regular File
DIR – Directory
FIFO – First In First Out
CHR – Character special file
For a complete list of FD & TYPE, refer man lsof.
2). List user specific opened files:
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lsof -u user_name
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3). List Process running on a port:
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lsof -i
ort_number
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4). Lists only IPv4 and IPv6 open files :
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lsof -i 4
lsof -i 6
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5). Lists open files for TCP port ranges 1-1024:
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lsof -i :1-1024
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6). Lists by pid:
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lsof -p PID
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7). Kill all activity for a particular user:
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killall -9 `lsof -t -u username`
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8). Lists Opened files in a directory:
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lsof +D /var/log/
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9). Lists Opened files based on process names:
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lsof -c process_name
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10). List all network connections:
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lsof -i
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11). Lists files Exclude User with ‘^’ Character:
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lsof -i -u^root
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12). List opened files based on process names starting with:
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lsof -c ssh -c init
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13). List all TCP or UDP connections:
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lsof -i tcp; lsof -i udp
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14). List all Network File System ( NFS ) files:
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lsof -N -u hoststud -a
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15). Combine more list options using OR/AND:
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lsof -u hoststud -c init
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LSOF is the short form of "LiSt Open Files".
It is a command line utility which is used to list the information about the files that are opened by various processes.
In unix, everything is considered as a file, ( pipes, sockets, directories, devices, etc.).
So by using lsof, you can get the information about any opened files.
1). List all open files:
This command will provide list of open files of all active processes.
------
lsof
------
By default One file per line is displayed. Most of the columns are self explanatory. We will explain the details about couple of cryptic columns (FD and TYPE).
FD – Represents the file descriptor. Some of the values of FDs are,
cwd – Current Working Directory
txt – Text file
mem – Memory mapped file
mmap – Memory mapped device
NUMBER – Represent the actual file descriptor. The character after the number i.e ‘1u’, represents the mode in which the file is opened. r for read, w for write, u for read and write.
TYPE – Specifies the type of the file. Some of the values of TYPEs are,
REG – Regular File
DIR – Directory
FIFO – First In First Out
CHR – Character special file
For a complete list of FD & TYPE, refer man lsof.
2). List user specific opened files:
-----
lsof -u user_name
-----
3). List Process running on a port:
-----
lsof -i
ort_number-----
4). Lists only IPv4 and IPv6 open files :
-----
lsof -i 4
lsof -i 6
-----
5). Lists open files for TCP port ranges 1-1024:
-----
lsof -i :1-1024
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6). Lists by pid:
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lsof -p PID
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7). Kill all activity for a particular user:
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killall -9 `lsof -t -u username`
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8). Lists Opened files in a directory:
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lsof +D /var/log/
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9). Lists Opened files based on process names:
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lsof -c process_name
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10). List all network connections:
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lsof -i
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11). Lists files Exclude User with ‘^’ Character:
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lsof -i -u^root
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12). List opened files based on process names starting with:
-----
lsof -c ssh -c init
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13). List all TCP or UDP connections:
-----
lsof -i tcp; lsof -i udp
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14). List all Network File System ( NFS ) files:
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lsof -N -u hoststud -a
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15). Combine more list options using OR/AND:
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lsof -u hoststud -c init
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