nfsen-ng

nfsen-ng is an in-place replacement for the ageing nfsen.

Used components

• Front end: jQuery, dygraphs, FooTable, ion.rangeSlider
• Back end: RRDtool, nfdump tools

TOC

• nfsen-ng
  • Installation
  • Configuration
    • Nfdump
  • CLI/Daemon
    • Daemon as a systemd service
  • Logs
  • API

Installation

Detailed installation instructions are available in INSTALL.md. Pull requests for additional distributions are welcome.

Software packages required:

• nfdump
• rrdtool
• git
• composer
• apache2
• php >= 8.1

Apache modules required:

• mod_rewrite
• mod_deflate
• mod_headers
• mod_expires

PHP modules required:

• mbstring
• rrd

Configuration

Note: nfsen-ng expects the profiles-data folder structure to be PROFILES_DATA_PATH/PROFILE/SOURCE/YYYY/MM/DD/nfcapd.YYYYMMDDHHII, e.g. /var/nfdump/profiles_data/live/source1/2018/12/01/nfcapd.201812010225.

The default settings file is backend/settings/settings.php.dist. Copy it to backend/settings/settings.php and start modifying it. Example values are in italic:

• general
  • ports: (array(80, 23, 22, ...)) The ports to examine. Note: If you use RRD as datasource and want to import existing data, you might keep the number of ports to a minimum, or the import time will be measured in moon cycles...
    • sources: (array('source1', ...)) The sources to scan.
    • db: (RRD) The name of the datasource class (case-sensitive).
  • frontend
    • reload_interval: Interval in seconds between graph reloads.
  • nfdump
    • binary: (/usr/bin/nfdump) The location of your nfdump executable
    • profiles-data: (/var/nfdump/profiles_data) The location of your nfcapd files
    • profile: (live) The profile folder to use
    • max-processes: (1) The maximum number of concurrently running nfdump processes. Note: Statistics and aggregations can use lots of system resources, even to aggregate one week of data might take more than 15 minutes. Put this value to > 1 if you want nfsen-ng to be usable while running another query.
  • db If the used data source needs additional configuration, you can specify it here, e.g. host and port.
  • log
    • priority: (LOG_INFO) see other possible values at [http://php.net/manual/en/function.syslog.php]

Nfdump

Nfsen-ng uses nfdump to read the nfcapd files. You can specify the location of the nfdump binary in backend/settings/settings.php. The default location is /usr/bin/nfdump.

You should also have a look at the nfdump configuration file /etc/nfdump.conf and make sure that the nfcapd files are written to the correct location. The default location is /var/nfdump/profiles_data.

Hhere is an example of an nfdump configuration:

options='-z -S 1 -T all -l /var/nfdump/profiles-data/live/<source> -p <port>'

where

• -z is used to compress the nfcapd files
• -S 1 is used to specify the nfcapd directory structure
• -T all is used to specify the extension of the nfcapd files
• -l is used to specify the destination location of the nfcapd files
• -p is used to specify the port of the nfcapd files.

Nfcapd x Sfcapd

To use sfcapd instead of nfcapd, you have to change the nfdump configuration file /lib/systemd/system/nfdump@.service to use sfcapd instead of nfcapd:

[Unit]
Description=netflow capture daemon, %I instance
Documentation=man:sfcapd(1)
After=network.target auditd.service
PartOf=nfdump.service

[Service]
Type=forking
EnvironmentFile=/etc/nfdump/%I.conf
ExecStart=/usr/bin/sfcapd -D -P /run/sfcapd.%I.pid $options
PIDFile=/run/sfcapd.%I.pid
KillMode=process
Restart=no

[Install]
WantedBy=multi-user.target

CLI + Daemon

The command line interface is used to initially scan existing nfcapd.* files, or to administer the daemon.

Usage:

./cli.php [ options ] import

or for the daemon

./cli.php start|stop|status

• Options:

  • -v Show verbose output

  • -p Import ports data as well Note: Using RRD this will take quite a bit longer, depending on the number of your defined ports.

  • -ps Import ports per source as well Note: Using RRD this will take quite a bit longer, depending on the number of your defined ports.

  • -f Force overwriting database and start fresh

  • Commands:

    • import Import existing nfdump data to nfsen-ng. Note: If you have existing nfcapd files, better do this overnight or over a week-end.
    • start Start the daemon for continuous reading of new data
    • stop Stop the daemon
    • status Get the daemon's status

  • Examples:

    • ./cli.php -f import Imports fresh data for sources

    • ./cli.php -f -p -ps import Imports all data

    • ./cli.php start Starts the daemon

Daemon as a systemd service

You can use the daemon as a service. To do so, you can use the provided systemd service file below. You can copy it to /etc/systemd/system/nfsen-ng.service and then start it with systemctl start nfsen-ng.

[Unit]
Description=nfsen-ng
After=network-online.target

[Service]
Type=simple
RemainAfterExit=yes
restart=always
startLimitIntervalSec=0
restartSec=2
ExecStart=su - www-data --shell=/bin/bash -c '/var/www/html/nfsen-ng/backend/cli.php start'
ExecStop=su - www-data --shell=/bin/bash -c '/var/www/html/nfsen-ng/backend/cli.php stop'

[Install]
WantedBy=multi-user.target

Now, you should reload and enable the service to start on boot with systemctl daemon-reload and systemctl enable nfsen-ng.

Logs

Nfsen-ng logs to syslog. You can find the logs in /var/log/syslog or /var/log/messages depending on your system. Some distributions might register it in journalctl. To access the logs, you can use tail -f /var/log/syslog or journalctl -u nfsen-ng

You can change the log priority in backend/settings/settings.php.

API

The API is used by the frontend to retrieve data. The API endpoints are documented in API_ENDPOINTS.md.