Perlbal::Manual::ManagUsertContributed Perl DocuPerlbal::Manual::Management(3)NAMEPerlbal::Manual::Management - Managing Perlbal on-the-fly
VERSION
Perlbal 1.78.
DESCRIPTION
How to configure a Perlbal "management" service for on-the-fly
configuration and debugging.
READ ME FIRST
Please read Perlbal::Manual::Configuration first for a better
explanation on how to configure Perlbal. This document will make much
more sense after reading that.
Setting up a management service
You can create a management service in the following way:
CREATE SERVICE mgmt
SET role = management
SET listen = 127.0.0.1:16000
ENABLE mgmt
Consulting information with a browser
If you access the management service (in this case, 127.0.0.1 on port
16000) with a browser you'll reach a page with information on the
services that are enabled. You're also able to click those services and
reach further information on each of them.
Managing Perlbal via telnet
If you telnet to the management service you get a connection that
allows you manage your Perlbal's instance.
$ telnet 127.0.0.1 16000
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
You now have access to several commands (which are case insensitive):
Admin Commands
create pool <name>
create service <name>
Creates a pool or a service.
create pool my_new_pool
create service my_new_service
disable <service>
Disables a service (stops listening).
disable my_service
Note that you can not disable "management" services.
enable <service>
Enables a service (starts listening).
enable my_service
header <service> insert <header>:<value>
header <service> remove <header>
Inserts or removes headers from the request before they're passed
on to the backend.
When adding headers you must state the value:
header my_service insert x-myamazingheader:myamazingvalue
When removing headers you don't need the state any value, the
header will be removed regardless of the value it holds:
header my_service remove Connection
Note: the usage of "x-" in the beginning of your header is not
required, but the convention is that non-standard headers be
prefixed with "x-".
load <plugin>
Loads a Perlbal plugin.
load AccessControl
plugins
Lists plugins
pool <name> add <ip[:port]>
pool <name> remove <ip[:port]>
Allows you to add or remove nodes from a service.
pool add my_service 127.0.0.1:1337
pool remove my_service 127.0.0.1:1337
Note that adding a node that already exists or removing a non-
existing node do not result in an error message.
Also note that the port number defaults to :80 if omitted.
reproxy_state
Dumps the state of reproxy status.
reproxy_state
SERVER max_reproxy_connections = 0
server <param> = <value>
Sets a server parameter, where param is one of:
· max_reproxy_connections = <value>
Maximum number of concurrent connections to the backends.
· max_reproxy_connections("ip") = <value>
Maximum number of concurrent connections to one specific
backend.
· max_connections = <value>
Sets the value of "RLIMIT_NOFILE" (maximum number of open
files for this process).
Requires BSD::Resource. Also, Perlbal must be run under a
superuser.
· nice_level = <value>
Sets the "nice" level for the process.
· aio_mode = <value>
One of "none", "linux" for Linux::AIO, or "ioaio" for
IO::AIO.
This controls how disk IO is done asynchronously. Highly
recommended to use Linux::AIO or IO::AIO for webserving or
reproxying files. For purely reverse proxy or only
reproxying URLs, none is fine.
· aio_threads = <value>
Number of child threads doing disk IO. Use between 2 and
50.
· track_obj = <value>
Developer option to track objects.
· pidfile = <value>
Filename to write pidfile to (no pidfile if not specified).
· crash_backtrace = <value>
1 or 0 indicating whether to perform a backtrace while the
server is crashing.
set [<pool_name>] <param> = <value>
Sets a property on a pool. If the pool was just created, specifying
the pool name is optional.
Setting the file to autoload nodes from (Perlbal will periodically
check the file for updates):
SET my_pool nodefile = /path/to/file
Unsetting the file to autoload nodes from (note that this does not
remove current members):
SET my_pool nodefile = none
"undef", "null", "" and '' are interpreted just like "none".
Note that manually modifying the pool (via POOL ADD or POOL REMOVE)
will disable the periodic checking of the nodefile.
Setting the load balancing method:
SET pool balance_method = 'random'
Yes, we do realize that "random" is the only method currently
available, but hey.
set [<service_name>] <param> = <value>
Sets a property on a service. If the service was just created,
specifying the service name is optional.
See Perlbal::Manual::LoadBalancer, Perlbal::Manual::ReverseProxy
and Perlbal::Manual::WebServer for the list of available
parameters.
show service [<service_name>]
show pool [<pool_name>]
List all services:
show service
Show details of a service:
show service my_service
Lists all pools, nodes and services using them:
show pool
Show the members of a pool:
show pool my_pool
shutdown [graceful]
Shuts down the server (you'll also lose your telnet session).
Can be used instantly, killing all active connections:
shutdown
Using the parameter "graceful" listening sockets are closed and
perlbal stays alive until clients bleed off.
shutdown graceful
unload <plugin>
Unloads a plugin.
unload AccessControl
use <service>
use <pool>
Sets the implied service or pool for future operations.
For instance, after:
use my_pool
You can just type:
pool add 127.0.0.1:6000
Note that creating a service or pool also sets it as the implied
service.
xs
xs [enable <module>]
xs [disable <module>]
Show status of XS modules loaded:
xs
Turn on an already-loaded XS module:
xs enable module_name
Turn off an already-loaded XS module:
xs disable module_name
Diagnostic Commands
aio Shows Perlbal::AIO stats.
backends
Lists the open connections to the backends.
backends
127.0.0.1:3080 1
127.0.0.1:3081 2
In the above example, there are 3 open connections (they may be
being used or they may simply be open according to the value of
"connect_ahead").
dumpconfig
Shows the current configuration for each service.
If a service uses a plugin that supports "dumpconfig", that
plugin's configuration is also dumped (see "dumpconfig" under
Perlbal::Manual::Plugins for more information).
fd Shows the maximum number of file descriptors and how many are
currently in use.
fd
max 1024
cur 8
gladiator
Requires Devel::Gladiator.
Iterate's Perl's internal memory structures and can be used to
enumerate all the currently live SVs.
This can be used to hunt leaks and to profile memory usage.
help
Displays the list of available commands.
leaks
leaks <code>
Iterates over active objects.
If an argument is specified, it is treated as code with $_ being
the reference to the object.
Shows objects that might have been leaked.
mime
Lists known mime types.
mime
css text/css
doc application/msword
...
node <ip[:port]>
Dumps information on a specific node.
node 127.0.0.1:8181
127.0.0.1:8181 attempts 10
127.0.0.1:8181 lastattempt 1290461126
Calling "node" with a parameter is the same as calling "nodes".
nodes
Dumps information on all nodes.
nodes
127.0.0.1:8181 attempts 10
127.0.0.1:8181 lastattempt 1290461126
127.0.0.1:8081 connects 19
127.0.0.1:8081 lastconnect 1290461127
127.0.0.1:8081 attempts 19
127.0.0.1:8081 responsecodes 200 11
127.0.0.1:8081 lastattempt 1290461127
noverify
Shows the amount of time left for each node marked as noverify.
If the "verify_backend" parameter is set to a true value, perlbal
tries to send an "OPTIONS" command to a node before sending it the
actual client request. If the node doesn't support the "OPTIONS"
command, the node is added to an internal hash so that an "OPTIONS"
command is not issued for new requests during the next 60 seconds.
noverify
127.0.0.1:8081 42
In the above example, node 127.0.0.1:8081 is on that list and still
has 42 seconds until an "OPTIONS" command is tried again.
If the time is a negative value it means that the "OPTIONS" command
will be issued before the next request.
obj Shows objects count in scope.
The environment variable "DEBUG_OBJ" must be set to a true value
(see "Environment Variables" under Perlbal::Manual::Configuration
for more information).
pending
Shows pending backend connections by service, node, and age.
proc
Shows CPU usage, current time, pid, and total requests processed.
prof on
prof off
prof data
Enables/disables profiling or dumps profile data.
queues
Shows status of all queues (normal, high priority and low priority)
for all enabled services.
queues
service_mywebsite-normal.age 1
service_mywebsite-normal.count 8
service_mywebsite-highpri.age 0
service_mywebsite-highpri.count 0
service_mywebsite-lowpri.age 0
service_mywebsite-lowpri.count 0
reload <plugin_name>
Reloads a plugin that supports reloading.
socks [all]
socks summary
Lists all sockets or shows a summary of the sockets (by default
lists all sockets).
socks
fd age
3 748s Perlbal::ClientManage(R): open to 85.245.86.253:52248
4 1003s Perlbal::TCPListener(R): open: listening on 82.102.30.112:80 for service 'ws'
6 1003s Perlbal::TCPListener(R): open: listening on 0.0.0.0:60000 for service 'mgmt'
socks summary
1 Perlbal::ClientManage
2 Perlbal::TCPListener
Aggregate write buffer: 0.0k
Open files: 0
state changes
Lists recent state changes of requests.
For instance, while a request is being processed this command may
issue something like:
state changes
Perlbal::ClientProxy=HASH(0x12d7ec28): reading_headers, wait_backend, backend_req_sent, wait_res
Perlbal::BackendHTTP=HASH(0x12d75f30): connecting, bored, sending_req, wait_res
wait_res 2
And as soon as the request is processed:
state changes
Perlbal::BackendHTTP=HASH(0x12d75f30): connecting, bored, sending_req, wait_res, xfer_res, closed
closed 1
Note: This functionality depends on the environment variable
"PERLBAL_TRACK_STATES" being set to a true value.
states
states <service>
Shows how many sockets of which type and in which state currently
exist for all services.
states
Perlbal::ClientProxy draining_res 1
If a service is specified, shows the information for that service
only.
states ws
Perlbal::BackendHTTP wait_res 1
Perlbal::ClientProxy wait_res 1
track
Dumps objects tracked, sorted by age.
track
15s Perlbal::HTTPHeaders=HASH(0x1a043a50): Perlbal::HTTPHeaders::clone, Perlbal::BackendHTTP::assign_client, Perlbal::Service::register_boredom, Perlbal::BackendHTTP::event_write, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
15s Perlbal::HTTPHeaders=HASH(0x19594fe0): Perlbal::HTTPHeaders::new, Perlbal::Socket::read_headers, Perlbal::Socket::read_response_headers, Perlbal::BackendHTTP::event_read_waiting_options, Perlbal::BackendHTTP::event_read, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
15s Perlbal::HTTPHeaders=HASH(0x1a043d80): Perlbal::HTTPHeaders::new, Perlbal::Socket::read_headers, Perlbal::Socket::read_response_headers, Perlbal::BackendHTTP::event_read, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
15s Perlbal::BackendHTTP=HASH(0x1a044608): Perlbal::BackendHTTP::new, Perlbal::Service::spawn_backends, Perlbal::Service::note_bad_backend_connect, Perlbal::BackendHTTP::event_err, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
15s Perlbal::BackendHTTP=HASH(0x1a042588): Perlbal::BackendHTTP::new, Perlbal::Service::spawn_backends, Perlbal::Service::note_bad_backend_connect, Perlbal::BackendHTTP::verify_failure, Perlbal::BackendHTTP::event_read_waiting_options, Perlbal::BackendHTTP::event_read, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
15s Perlbal::BackendHTTP=HASH(0x1a044488): Perlbal::BackendHTTP::new, Perlbal::Service::spawn_backends, Perlbal::Service::request_backend_connection, Perlbal::ClientProxy::request_backend, Perlbal::ClientProxy::handle_request, Perlbal::ClientProxy::event_read, Danga::Socket::EpollEventLoop, (eval), Perlbal::run
For this to work you must have the environment variable "DEBUG_OBJ"
set to a true value and the server option "track_obj" on:
server track_obj = 1
OK
uptime
version
Shows the time the server was started, the current uptime and
Perlbal's version.
varsize
Debug management command to track size of internal data structures.
varsize
svc-ws-bored_backends [] 2
svc-ws-pending_connects {} 2
{127.0.0.1:3080} =
{127.0.0.1:3081} = Perlbal::BackendHTTP=HASH(0x1cfd2490)
verbose on
verbose off
Turns verbose mode on or off.
verbose on
load AccessControl
OK
verbose off
load AccessControl
verbose on
OK
load AccessControl
OK
Yes, verbose mode only activates the printing of an OK message upon
completion of some commands such as "load". Errors are displayed
regardless of verbose status.
CAVEAT
Note that this functionality doesn't implement any sort of
authentication. If you can telnet to the address you specify, you can
access the information and change things on the fly.
Some alternatives to authentication are commonly employed:
· specifying the address as being 127.0.0.1 means that no one outside
the machine can telnet to the management service;
· setting the management address as a private IP available only
through a VPN, for instance, will allow you to manage these
accesses on the VPN instead.
SEE ALSO
Perlbal::Manual::Configuration, Perlbal::Manual::Debugging.
perl v5.14.2 2011-01-23 Perlbal::Manual::Management(3)
