pmproxy - proxy for performance metrics collector and
querying
pmproxy [-AdfFt?] [-c conffile]
[-h host[,host ...] [-i ipaddress]
[-l logfile] [-L bytes] [-p
port[,port ...] [-r port[,port ...]
[-s sockname] [-U username] [-x
outfile]
pmproxy acts as a protocol proxy, allowing Performance
Co-Pilot (PCP) monitoring clients to connect to one or more pmcd(1)
and/or redis-server(1) instances via pmproxy.
In its default mode of operation, on platforms supporting this,
pmproxy provides the REST API for all PCP services (see
PMWEBAPI(3) for details) and interfaces to the fast, scalable time
series query capabilities offered by PCP in conjunction with a
redis-server(1) (see pmseries(1) for details).
pmproxy can be deployed in a firewall domain, or on a
cluster ``head'' node where the IP (Internet Protocol) address of the hosts
where pmcd and/or redis-server are running may be unknown to
the PCP monitoring clients, but where the IP address of the host running
pmproxy is known to these clients. Similarly, the clients may have
network connectivity only to the host where pmproxy is running, while
there is network connectivity from that host to the hosts of interest where
pmcd and/or redis-server are running.
The behaviour of the PCP monitoring clients is controlled by
either the PMPROXY_HOST environment variable or through the extended
hostname specification (see PCPIntro(1) for details). If neither of
these mechanisms is used, clients will make their PMAPI(3)
connections directly to pmcd. If the proxy hostname syntax is used or
PMPROXY_HOST is set, then this should be the hostname or IP address
of the system where pmproxy is running, and the clients will connect
to pmcd or redis-server indirectly through the protocol proxy
services of pmproxy.
The available command line options are:
- -A
- Disable service advertisement. By default, pmproxy will advertise
its presence on the network using any available mechanisms (such as
Avahi/DNS-SD), assisting remote monitoring tools with finding it. These
mechanisms are disabled with this option.
- -c conffile,
--config=conffile
- Specify the path to an optional configuration conffile, with format
as described in the ``CONFIGURATION'' section. This option implies
pmproxy is running in timeseries mode.
- -d,
--deprecated
- By default pmproxy prefers to run in the new timeseries
mode, providing REST APIs, asynchronous network I/O, scalable time series,
and secure connections using OpenSSL. However, legacy deployments may wish
to use the original synchronous pmproxy implementation using libpcp
networking; this can be achieved using this option. Note that the
-d and -t options are mutually exclusive.
- -f,
--foreground
- By default pmproxy is started as a daemon. The -f option
indicates that it should run in the foreground. This is most useful when
trying to diagnose problems with establishing connections.
- -F, --systemd
- Like -f, the -F option runs pmproxy in the
foreground, but also does some housekeeping (like create a ``pid'' file
and change user id). This is intended for use when pmproxy is
launched from systemd(1) and the daemonizing has already been done
by systemd(1) and does not need to be done again by pmproxy,
which is the case when neither -f nor -F is specified.
At most one of -f and -F may be specified.
- -h host,
--redishost=host
- Specify an alternate Redis host to connect to for time series
querying, overriding any configuration file settings. This option implies
pmproxy is running in timeseries mode.
- -i ipaddress,
--interface=ipaddress
- This option is usually only used on hosts with more than one network
interface (very common for firewall and ``head'' node hosts where
pmproxy is likely to be deployed to arbitrate access to an internal
network). If no -i options are specified pmproxy accepts PCP
client connections on any of its host's IP addresses. The -i option
is used to specify explicitly an IP address that PCP client connections
should be accepted on. ipaddress should be in the standard dotted
form (e.g. 100.23.45.6). The -i option may be used multiple times
to define a list of IP addresses. When one or more -i options is
specified, attempted connections made on any other IP addresses will be
refused.
- -l logfile,
--log=logfile
- By default a log file named pmproxy.log is written in the current
directory. The -l option causes the log file to be written to a
given logfile instead of the default. If this logfile cannot
be created or is not writable, output is written to the standard error
instead.
- -L bytes
- PDUs received by pmproxy from PCP monitoring clients are
restricted to a maximum size of 65536 bytes by default to defend against
Denial of Service attacks. The -L option may be used to change the
maximum incoming PDU size.
- -p port,
--port=port
- Specify an alternate port number to listen on for client
connections. The default value is 44322.
- -r port,
--redisport=port
- Specify an alternate Redis port number to connect to for time
series querying, overriding any configuration file settings. This option
implies pmproxy is running in timeseries mode.
- -s sockname,
--socket=sockname
- Specify the path to a local unix domain socket (for platforms supporting
this socket family only). The default value is
$PCP_RUN_DIR/pmproxy.socket. This option implies pmproxy is
running in timeseries mode.
- -t,
--timeseries
- Operate in automatic archive timeseries discovery mode. This mode of
operation will enable the PMWEBAPI(3) REST APIs, dynamiclly and
automatically detect active system archives being written by
pmlogger(1) and import them into a redis-server(1), for
fast, scalable time series querying described in pmseries(1). Note
that in this mode of operation, pmproxy only "log-tails"
and ingests actively growing archives, e.g. as written by one or more
pmlogger(1) instances. When an archive is first discovered (usually
but not limited to pmproxy startup), all metadata is loaded and
sent to the configured redis-server(1) however note that only
new archive metric value data from the tail end of each archive is
ingested. Compressed archives never grow and so are ignored. See the
--load option to pmseries(1) for a supported mechanism for
manually loading all of the metric value data from previously collected
(inactive) archives, whether compressed or not. It would be normal, though
not mandated, for a set of archives being manually loaded to cover the
same time period, e.g. archive data for a particular week for one or more
hosts in the same data-centre.
- -U username,
--username=username
- Assume the identity of the given username before starting to accept
incoming packets from PCP monitoring clients.
- -x outfile
- Before the pmproxy logfile can be opened, pmproxy may
encounter a fatal error which prevents it from starting. By default the
output describing this error is sent to /dev/tty but it may
redirected to outfile.
- -?, --help
- Display usage message and exit.
When running in the timeseries mode of operation, runtime
configuration is relatively complex and typically handled via the
$PCP_SYSCONF_DIR/pmproxy/pmproxy.conf file. This file is in the
common ``ini'' format, with section headers and individual variables and
values with each section. The configuration file installed as part of PCP
documents every available section and option.
At a high level, the [pmproxy] section can be used to
explicitly enable or disable each of the different protocols.
The [redis] section allows connection information for one
or more backing redis-server processes to be configured (hostnames
and ports). Note to access multiple (scalable) Redis servers, the
servers variable in this section can be a comma-separated list of
hostname:port pairs. Alternatively, it can be a single redis-server
host that will be queried using the "CLUSTER INFO" command to
automatically configure multiple backing hosts, described at
https://redis.io/topics/cluster-spec.
In earlier versions of PCP (before 6) an alternative configuration
setting section was used for this purpose - Redis servers were
specified in the [pmseries] section and this is still accepted as a
fallback for backwards compatibility.
Normally, pmproxy is started automatically at boot time and
stopped when the system is being brought down. Under certain circumstances
it is necessary to start or stop pmproxy manually. To do this one
must become superuser and type
# $PCP_RC_DIR/pmproxy start
to start pmproxy, or
# $PCP_RC_DIR/pmproxy stop
to stop pmproxy. Starting pmproxy when it is already
running is the same as stopping it and then starting it again.
Normally pmproxy listens for PCP client connections on
TCP/IP port number 44322 (as well as 44323 with timeseries enabled)
registered at https://www.iana.org/. Either the environment variable
PMPROXY_PORT or the -p command line option may be used to
specify alternative port number(s) when pmproxy is started; in each
case, the specification is a comma-separated list of one or more numerical
port numbers. Should both methods be used or multiple -p options
appear on the command line, pmproxy will listen on the union of the
set of ports specified via all -p options and the PMPROXY_PORT
environment variable. If non-default ports are used with pmproxy care
should be taken to ensure that PMPROXY_PORT is also set in the
environment of any client application that will connect to pmproxy,
or that the extended host specification syntax is used (see
PCPIntro(1) for details).
If pmproxy is already running the message "Error:
OpenRequestSocket bind: Address already in use" will appear. This may
also appear if pmproxy was shutdown with an outstanding request from
a client. In this case, a request socket has been left in the TIME_WAIT
state and until the system closes it down (after some timeout period) it
will not be possible to run pmproxy.
In addition to the standard PCP debugging options, see
pmdbg(1), pmproxy currently supports the debugging option
context for tracing client connections and disconnections.
- $PCP_PMPROXYOPTIONS_PATH
- command line options for pmproxy when launched from
$PCP_RC_DIR/pmproxy All the command line option lines should start
with a hyphen as the first character.
- $PCP_SYSCONFIG_DIR/pmproxy
- Environment variables that will be set when pmproxy executes. Only
settings of the form "PMPROXY_VARIABLE=value" will be
honoured.
- ./pmproxy.log
- (or $PCP_LOG_DIR/pmproxy/pmproxy.log when started automatically)
All messages and diagnostics are directed here
- /etc/pki/tls
- default OpenSSL certificate database directory, optionally used for Secure
Socket Layer connection in timeseries mode of operation. These
certificates can be created and queried using the openssl tool,
amongst others.
In addition to the PCP environment variables described in the
PCP ENVIRONMENT section below, there are several environment
variables that influence the interactions between a PCP monitoring client,
pmproxy and pmcd.
- PMCD_PORT
- For the PCP monitoring client this (or the default port number) is passed
to pmproxy and used to connect to pmcd. In the environment
of pmproxy PMCD_PORT is not used.
- PMPROXY_HOST
- For the PCP monitoring client this is the hostname or IP address of the
host where pmproxy is running. In recent versions of PCP (since
version 3) this has been superseded by the extended hostname syntax (see
PCPIntro(1) for details).
- PMPROXY_PORT
- For the PCP monitoring client this is the port on which pmproxy
will accept connections. The default is 44322, as well as 44323 with
timeseries enabled.
- PMCD_CONNECT_TIMEOUT,
PMCD_RECONNECT_TIMEOUT and PMCD_REQUEST_TIMEOUT
- (see PCPIntro(1)) For the PCP monitoring client, setting these
environment variables will modify the timeouts used for interactions
between the client and pmproxy (independent of which pmcd is
being used). For pmproxy these same environment variables control
the timeouts between pmproxy and all pmcd(1) instances
(independent of which monitoring client is involved).
If set to the value 1, the PMPROXY_LOCAL environment
variable will cause pmproxy to run in a localhost-only mode of
operation, where it binds only to the loopback interface.
The PMPROXY_MAXPENDING variable can be set to indicate the
maximum length to which the queue of pending client connections may
grow.
Environment variables with the prefix PCP_ are used to
parameterize the file and directory names used by PCP. On each installation,
the file /etc/pcp.conf contains the local values for these variables.
The $PCP_CONF variable may be used to specify an alternative
configuration file, as described in pcp.conf(5).
For environment variables affecting PCP tools, see
pmGetOptions(3).