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Version: Cloud

Monitor List of Open Files (LSOF)


LSOF (list open files) Metric plugin collects data for number of files opened by a process of different file descriptor types.

Prerequisite - Install lsof Command

lsof command needs to be installed before running this plugin.

To install lsof in Centos / RHEL

sudo yum install lsof

To install lsof in Ubuntu

sudo apt-get install lsof

To verify installation, run the below command.

lsof -v

Expected output:

lsof version information: 
revision: 4.87
latest revision:
latest FAQ:
latest man page:
constructed: Tue Oct 30 16:28:19 UTC 2018
constructed by and on:
compiler: cc
compiler version: 4.8.5 20150623 (Red Hat 4.8.5-36) (GCC)
compiler flags: -DLINUXV=310000 -DGLIBCV=217 -DHASIPv6 -DHASSELINUX -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE -DHAS_STRFTIME -DLSOF_VSTR="3.10.0" -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic
loader flags: -L./lib -llsof -lselinux
system info: Linux 3.10.0-693.17.1.el7.x86_64 #1 SMP Thu Jan 25 20:13:58 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

version may vary depending upon the Linux distribution.

Agent Configuration

Refer to sfAgent section for steps to install and automatically generate plugin configurations. User can also manually add the configuration shown below to config.yaml under /opt/sfagent/ directory

key: <profile_key> 
Name: <name>
appName: <app_name>
projectName: <project_name>
- name: lsof
enabled: true
interval: 600
completeStats: false
numProcess: 5
sortFilter: DIR

Configuration Details

LSOF plugin runs in two different modes: summary and complete stats.

  • In summary mode, plugin returns only the count of files open of each file descriptor type (like DIR, CHR, REG etc.) at an aggregate level. Set completeStats: false for summary mode
  • In completeStats mode, plugin returns the entire list of open files in the machine, process wise along with the process id. Set completeStats: true for this mode. Since the list of all opened files can be huge in number, plugin is by default configured in summary mode

Other configuration parameters include:

  • numProcess: Number of top N processes with maximum number of files opened. For example, if numProcess is set to 5, it returns top 5 process stats with maximum number of files opened. Set numProcess to 0 to get all process details. Default value is 10.
  • sortFilter: Selection of top N processes only for a particular file descriptor type. Following are the options available: none, CHR, DIR, REG, FIFO, IP, netlink, socket, a_inode. Default value is none. For example, to get top 10 processes with maximum directories opened, numProcess should be set to 10 and sortFilter as DIR. Set sort filter to none if no sorting is required.

All the traffic related (IPv4, IPv6) file types are combined as IPv4/6 type and unix sockets into socket type

Viewing data and dashboards

  • Data collected by plugins can be viewed in SnappyFlow’s browse data section under metrics section
    • plugin: lsof
    • documentType: lsofSummary, lsofstats
    • Dashboard template: LSOF

Test Matrix

  • Centos: 7.x

  • RHEL: 7.x

  • Ubuntu: 14.x, 16.x

See Also