Ubuntu Manpage: keepalived - load-balancing and high-availability service

NAME

       keepalived - load-balancing and high-availability service

SYNOPSIS

       keepalived [-f|--use-file=FILE] [-P|--vrrp] [-C|--check] [-B|--no_bfd] [--all]
       [-l|--log-console] [-D|--log-detail] [-S|--log-facility={0-7|local{0-7}|user|daemon}]
       [-g|--log-file=FILE] [--flush-log-file] [-G|--no-syslog] [-X|--release-vips]
       [-V|--dont-release-vrrp] [-I|--dont-release-ipvs] [-R|--dont-respawn] [-n|--dont-fork]
       [-d|--dump-conf] [-p|--pid=FILE] [-r|--vrrp_pid=FILE] [-T|--genhash]
       [-c|--checkers_pid=FILE] [-a|--address-monitoring] [-b|--bfd_pid=FILE]
       [-s|--namespace=NAME] [-e|--all-config] [-i|--config-id id] [-x|--snmp] [-A|--snmp-agent-
       socket=FILE] [-u|--umask=NUMBER] [-m|--core-dump] [-M|--core-dump-pattern[=PATTERN]]
       [--signum=SIGFUNC] [-t|--config-test[=FILE]] [--perf[={all|run|end}]] [--debug[=debug-
       options]] [--no-mem-check] [-v|--version] [-h|--help]

DESCRIPTION

       Keepalived provides simple and robust facilities for load-balancing and high-availability.
       The load-balancing framework relies on the well-known and widely used Linux Virtual Server
       (IPVS) kernel module providing Layer4 load-balancing. Keepalived implements a set of
       checkers to dynamically and adaptively maintain and manage a load-balanced server pool
       according to their health. Keepalived also implements the VRRPv2 and VRRPv3 protocols to
       achieve high-availability with director failover.

OPTIONS

-f, --use-file=FILE
Use the specified configuration file. The default configuration file is
"/etc/keepalived/keepalived.conf".

-P, --vrrp
Only run the VRRP subsystem. This is useful for configurations that do not use the
IPVS load balancer.

-C, --check
Only run the healthcheck subsystem. This is useful for configurations that use the
IPVS load balancer with a single director with no failover.

-B, --no_bfd
Don't run the BFD subsystem.

--all Run all subsystems, even if they have no configuration.

-l, --log-console
Log messages to the local console. The default behavior is to log messages to
syslog.

-D, --log-detail
Detailed log messages.

-S, --log-facility={0-7|local{0-7}|user|daemon}
Set syslog facility to LOG_LOCAL[0-7], LOG_USER or LOG_DAEMON. The default syslog
facility is LOG_DAEMON.

-g, --log-file=FILE
Write log entries to FILE. FILE will have _vrrp, _healthcheckers, and _bfd inserted
before the last '.' in FILE for the log output for those processes.

--flush-log-file
If using the -g option, the log file stream will be flushed after each write.

-G, --no-syslog
Do not write log entries to syslog. This can be useful if the rate of writing log
entries is sufficiently high that syslog will rate limit them, and the -g option is
used instead.

-X, --release-vips
Drop VIP on transition from signal.

-V, --dont-release-vrrp
Don't remove VRRP VIPs and VROUTEs on daemon stop. The default behavior is to
remove all VIPs and VROUTEs when keepalived exits.

-I, --dont-release-ipvs
Don't remove IPVS topology on daemon stop. The default behavior it to remove all
entries from the IPVS virtual server table when keepalived exits.

-R, --dont-respawn
Don't respawn child processes. The default behavior is to restart the VRRP and
checker processes if either process exits.

-n, --dont-fork
Don't fork the daemon process. This option will cause keepalived to run in the
foreground.

-d, --dump-conf
Dump the configuration data.

-p, --pid=FILE
Use the specified pidfile for the parent keepalived process. The default pidfile
for keepalived is "/run/keepalived.pid", unless a network namespace is being used.
See NAMESPACES below for more details.

-r, --vrrp_pid=FILE
Use the specified pidfile for the VRRP child process. The default pidfile for the
VRRP child process is "/run/keepalived_vrrp.pid", unless a network namespace is
being used.

-T, --genhash
Enter genhash utility mode. Previous versions of keepalived were shipped with a
dedicated genhash utility. genhash is now part of the mainline code. We keep
compatibility with previous genhash utility command line option. For more
information please refer to the genhash(1) manpage.

-c, --checkers_pid=FILE
Use the specified pidfile for checkers child process. The default pidfile for the
checker child process is "/run/keepalived_checkers.pid" unless a network namespace
is being used.

-a, --address-monitoring
Log all address additions/deletions reported by netlink.

-b, --bfd_pid=FILE
Use the specified pidfile for the BFD child process. The default pidfile for the
BFD child process is "/run/keepalived_bfd.pid" unless a network namespace is being
used.

-s, --namespace=NAME
Run keepalived in network namespace NAME. See NAMESPACES below for more details.

-e, --all-config
Don't load if any configuration file is missing or cannot be read.

-i, --config-id ID
Use configuration id ID, for conditional configuration (defaults to hostname
without the domain name).

-x, --snmp
Enable the SNMP subsystem.

-A, --snmp-agent-socket=FILE
Use the specified socket for connection to SNMP master agent.

-u, --umask=NUMBER
The umask specified in the usual numeric way - see man umask(2)

-m, --core-dump
Override the RLIMIT_CORE hard and soft limits to enable keepalived to produce a
coredump in the event of a segfault or other failure. This is most useful if
keepalived has been built with 'make debug'. Core dumps will be created in /,
unless keepalived is run with the --dont-fork option, in which case they will be
created in the directory from which keepalived was run, or they will be created in
the directory of a configuraton file if the fault occurs while reading the file.

-M, --core-dump-pattern[=PATTERN]
Sets option --core-dump, and also updates /proc/sys/kernel/core_pattern to the
pattern specified, or 'core' if none specified. Provided the parent process
doesn't terminate abnormally, it will restore /proc/sys/kernel/core_pattern to its
original value on exit.

Note: This will also affect any other process producing a core dump while
keepalived is running.

--signum=PATTERN
Returns the signal number to use for STOP, RELOAD, DATA, STATS, STATS_CLEAR, JSON
and TDATA. For example, to stop keepalived running, execute:

kill -s $(keepalived --signum=STOP) $(cat /run/keepalived.pid)

-t, --config-test[=FILE]
Keepalived will check the configuration file and exit with non-zero exit status if
there are errors in the configuration, otherwise it exits with exit status 0 (see
Exit status below for details).

Rather that writing to syslog, it will write diagnostic messages to stderr unless
file is specified, in which case it will write to the file.

--perf[={all|run|end}]
Record perf data for vrrp process. Data will be written to /perf_vrrp.data. The
data recorded is for use with the perf tool.

--no-mem-check
Disable malloc() etc mem-checks if they have been compiled into keepalived.

--debug[=debug-options]]
Enables debug options if they have been compiled into keepalived. debug-options is
made up of a sequence of strings of the form Ulll.
The upper case letter specifies the debug option, and the lower case letters
specify for which processes the option is to be enabled.
If a debug option is not followed by any lower case letters, the debug option is
enabled for all processes.

The characters to identify the processes are:

Chr Process
──────────────────────
p Parent process
b BFD process
c Checker process
v VRRP process

The characters used to identify the debug options are:

Chr Debug option
────────────────────────────────────────────
D Epoll thread dump
E Epoll debug
F VRRP fd debug
N Netlink timers
P Network timestamp
X Regex timers
M Email alert debug
T Timer debug
S TSM debug
R Regex debug
B Smtp connect debug
U Checksum diagnostics
O Track process debug
A Track process debug with extra detail
C Parser (config) debug
H Checker debug
Z Memory alloc/free error debug
G VRRP recvmsg() debug
J VRRP recvmsg() log rx data
V Script debugging
K Dump keywords

Example: --debug=DvEcvNR

-v, --version
Display the version and exit.

-h, --help
Display this help message and exit.

Exit status:
0 if OK

1 if unable to malloc memory

2 if cannot initialise subsystems

3 if running with --config-test and configuration cannot be run

4 if running with --config-test and there are configuration errors but keepalived
will run after modifying the configuration

5 if running with --config-test and script security hasn't been enabled but scripts
are configured.

NAMESPACES

       keepalived can be run in a network namespace (see keepalived.conf(5) for configuration
       details). When run in a network namespace, a local mount namespace is also created, and
       /run/keepalived/keepalived_NamespaceName is mounted on /run/keepalived. By default, pid
       files with the usual default names are then created in /run/keepalived from the
       perspective of a process in the mount namespace, and they will be visible in
       /run/keepalived/keepalived_NamespaceName for a process running in the default mount
       namespace.

SIGNALS

       keepalived reacts to a set of signals.  You can send a signal to the parent keepalived
       process using the following:

              kill -SIGNAL $(cat /run/keepalived.pid)

       or better:

              kill -s $(keepalived --signum=SIGFUNC) $(cat /run/keepalived.pid)

       Note that if the first option is used, -SIGNAL must be replaced with the actual signal you
       are trying to send, e.g. with HUP. So it then becomes:

              kill -HUP $(cat /run/keepalived.pid)

       Signals other than for STOP, RELOAD, DATA and STATS may change depending on the kernel,
       and also what functionality is included in the version of the keepalived depending on the
       build options used.

       HUP or SIGFUNC=RELOAD
              This causes keepalived to close down all interfaces, reload its configuration, and
              start up with the new configuration.

              Note: If a virtual_ipaddress, virtual_route or virtual_rule is being moved from one
              VRRP instance to another one, two reloads will be necessary, the first to remove
              the virtual ipaddress/route/rule, and the second reload to add it to the VRRP
              instance it is now to be configured on. Failing to do this can result in the
              ipaddress/route/rule not being configured on the new instance if both the old and
              new instances are in master state.  It will usually work with a single reload,
              however, if either of the VRRP instances is not in MASTER state or if the VRRP
              instance the ipaddress/route/rule the VRRP instance is being added to is later in
              the original configuration file than the instance it is being removed from.

       TERM, INT or SIGFUNC=STOP
              keepalived will shut down.

       USR1 or SIGFUNC=DATA
              Write configuration data to /tmp/keepalived.data

       USR2 or SIGFUNC=STATS
              Write statistics info to /tmp/keepalived.stats

       SIGFUNC=STATS_CLEAR
              Write statistics info to /tmp/keepalived.stats and clear the statistics counters

       SIGFUNC=JSON
              Write configuration data in JSON format to /tmp/keepalived.json

       SIGFUNC=TDATA
              This causes keepalived to write the current state of its internal threads to the
              log

USING KEEPALIVED WITH FIREWALLD

       If you are running a firewall (see firewalld(8)) you must allow VRRP protocol traffic
       through the firewall. For example if this instance of keepalived(8) has a peer node on
       IPv4 address 192.168.0.1:

              # firewall-cmd \
                  --add-rich-rule="rule family='ipv4' \
                                   source address='192.168.0.1' \
                                   protocol value='vrrp' accept" --permanent
              # firewall-cmd --reload

AUTHOR

       This man page was written by Ryan O'Hara <rohara@redhat.com>

                                            2022-01-06                              KEEPALIVED(8)