lookupd(8) BSD System Manager's Manual lookupd(8)NAMElookupd — directory information and cache daemon
SYNOPSISlookupd
lookupd -d
lookupd-D portname
lookupd-f category key value
lookupd-q category [[-a key [value ...]] ...]
lookupd-configuration
lookupd-flushcache
lookupd-statistics
DESCRIPTION
The lookupd daemon acts as an information broker and cache. It is called
by various routines in the System framework to find information about
user accounts, groups, printers, e-mail aliases and distribution lists,
computer names, Internet addresses, and several other kinds of informa‐
tion.
lookupd keeps a cache of recently requested items to improve system per‐
formance. It also implements a search strategy used to find information
from the many information sources that are potentially available to a
computer. These include the Domain Name System (DNS), Sun Microsystem's
Network Information Services (NIS), Apple's NetInfo system, and a set of
files found in the /etc directory. lookupd also has a channel to query
Directory Services, allowing access to data from LDAP and other directory
systems.
The lookupd process is monitored by the system's mach server registry
(the mach_init process), and is automatically restarted if it crashes or
exits. lookupd responds to a HUP signal by exiting. This is the pre‐
ferred mechanism for restarting / resetting the process.
lookupd writes its process ID number in the file /var/run/lookupd.pid.
LOOKUP STRATEGY
Internally, lookupd uses a set of software “agents” to get information.
There are agents for NetInfo, NIS, DNS, the files in /etc (also known as
the “Flat Files” ), Directory Services, and an agent which manages the
internal cache. There is also a special agent (the NILAgent) which
returns negative entries.
When lookupd searches for information about an item, it queries agents in
a specific order until the item is found or until all sources of informa‐
tion have been consulted without finding the desired item. By default,
lookupd first queries its cache agent, then NetInfo, then the Directory
Services agent. If the item is a host or network, lookupd will query the
cache, the Flat File agent, then the DNS agent, then NetInfo, and Direc‐
tory Services last. The default search order for services, protocols,
and rpc protocols uses the cache, then the Flat File agent, NetInfo, and
then Directory Services.
In some cases, lookupd creates lists of all the information available
about some sort of entity. For example, all printers or all users. In
these cases lookupd queries each agent in turn and concatenates all
retrieved information into a single list.
The search order is configurable. For example, you might specify that
lookupd queries its internal cache, then NetInfo, then the Flat Files,
then NIS. You may also change the lookup order for a particular category
of item. The known categories are users, groups, hosts, networks, ser‐
vices, protocols, rpcs, mounts, printers, bootparams, bootp, aliases, and
netgroups. You can set the lookup order (and other configuration
options) for all categories, and override them for individual categories.
Details on configuring lookupd are found in the CONFIGURATION section
below.
Some agents may have their own configuration options. Details on config‐
uring individual agents are found in the AGENTS section below.
CACHE
There are caches for all categories of lookups. The caches are unlimited
in capacity (although you can set a maximum size, see below). The
default lookup order starts with the cache agent for each lookup cate‐
gory. Caching may be disabled for all categories or for specific cate‐
gories by removing the cache agent from the lookup order.
CACHE VALIDATION
lookupd validates items retrieved from cache before returning them. If
an entry is invalid, a fresh copy is fetched to replace the stale one in
cache. In many cases it is possible for lookupd to quickly determine
that a cached entry is still valid; for example by checking a time stamp
or a database sequence number. When cache validation is enabled, perfor‐
mance is enhanced because many items can be stored in cache, while at the
same time clients can be certain that any data they get from lookupd is
as up-to-date as possible. If cache validation is disabled, items are
returned from cache without any checks. In this case it is possible that
the information is out-of-date. You can place limits on how stale an
item might be by setting the cache TimeToLive (see below).
You can also get the best of both worlds by having cache validation
enabled and adjusting the ValidationLatency. If an agent has just
fetched a database version number or read a time stamp in order to vali‐
date one item in the cache, then it can use that value for a few seconds
to validate other entries in the cache with only a small risk that those
entries have become out-of-date. Setting ValidationLatency to 0 seconds
causes validation on every fetch from cache. Setting the value to a
larger number means that lookupd will avoid re-checking time stamps,
sequence numbers, version numbers or other validation indicators for the
indicated number of seconds. This allows you to say, for example, that
you are willing to let the cache return an item that might be no more
than a few seconds out-of-date in order to reduce network traffic. The
default value for ValidationLatency is 15 seconds.
Validation is enabled by default, but may be disabled for all categories,
or for specific categories. For example, since computer names and
addresses very rarely change, you might want to turn off cache validation
for the host cache to save time and reduce network traffic. This is
especially useful on slow network lines. If network access is fast,
cache validation is inexpensive, and ensures that all data is up-to-date.
The cache validation strategy in the NetInfo and Flat File agents makes
validation as fast and inexpensive as possible. DNS validation is based
on the time-to-live value found in the DNS record for a particular item.
The NILAgent returns a negative record for any lookup. This stops fur‐
ther search for an item. The NILAgent should always appear last in any
LookupOrder specification (see below). The value of these negative
records is that they will be added to the cache (if caching is enabled).
If a lookup for a particular item fails (after a long, slow search of all
available information sources), then subsequent lookups for the same item
will find the negative record in the cache, thus avoiding another long
search. Like all other cached records, negative records are validated.
By default, negative records are valid for 60 seconds. You can override
the default by setting the TimeToLive option in the NILAgent's configura‐
tion. See the AGENT section below.
When an object is placed in a cache, it is given a time to live. After
that time has expired, it will be removed from the cache. The default is
12 hours. Making things expire more quickly will cause the cache to stay
smaller, but will result in more network traffic. Whenever an object is
validated, its time to live is reset.
CONFIGURATION
Configuration parameters may be placed in a set of files in the local
file system, or they may be written in a set of directories in NetInfo.
These parameters will override default settings. There may be one file
or one configuration directory in NetInfo for each agent, and one file or
NetInfo directory for each lookup category. There may also be a global
configuration file or NetInfo directory. Additionally, each agent may
have category-specific configuration.
lookupd searches for configuration in the local file system first. If no
configuration is given in the file system, lookupd checks for a configu‐
ration directory in NetInfo, starting at the local domain and climbing to
the root domain.
The configuration source may be specified on the command line as a
startup option. The configuration source may be specified using one of
the following command-line options:
-c default
-c file path
-c netinfo domain path
FILE-BASED CONFIGURATION
Configuration settings for lookup may be placed in files under the direc‐
tory /etc/lookupd. A file named “global” is used to store global set‐
tings for lookupd and for individual agents. Other files specify set‐
tings for each lookup category. It is not necessary to create every con‐
figuration file. Just create those in which you wish to override the
default values of configuration parameters. The files that may be cre‐
ated are:
/etc/lookupd/global
/etc/lookupd/users
/etc/lookupd/groups
/etc/lookupd/hosts
/etc/lookupd/networks
/etc/lookupd/services
/etc/lookupd/protocols
/etc/lookupd/rpcs
/etc/lookupd/mounts
/etc/lookupd/printers
/etc/lookupd/bootparams
/etc/lookupd/bootp
/etc/lookupd/aliases
/etc/lookupd/netgroups
/etc/lookupd/agents
/etc/lookupd/agents/CacheAgent/global
/etc/lookupd/agents/DNSAgent/global
/etc/lookupd/agents/FFAgent/global
/etc/lookupd/agents/NIAgent/global
/etc/lookupd/agents/NILAgent/global
/etc/lookupd/agents/NISAgent/global
Category-specific configuration files may appear in an agent's subdirec‐
tory. For example, category-specific files for NIAgent are:
/etc/lookupd/agents/NIAgent/global
/etc/lookupd/agents/NIAgent/users
/etc/lookupd/agents/NIAgent/groups
/etc/lookupd/agents/NIAgent/hosts
/etc/lookupd/agents/NIAgent/networks
/etc/lookupd/agents/NIAgent/services
/etc/lookupd/agents/NIAgent/protocols
/etc/lookupd/agents/NIAgent/rpcs
/etc/lookupd/agents/NIAgent/mounts
/etc/lookupd/agents/NIAgent/printers
/etc/lookupd/agents/NIAgent/bootparams
/etc/lookupd/agents/NIAgent/bootp
/etc/lookupd/agents/NIAgent/aliases
/etc/lookupd/agents/NIAgent/netgroups
Note that only some agents make use of category-specific configurations.
They are described in the AGENTS section below.
NETINFO-BASED CONFIGURATION
Configuration directories in NetInfo must be placed in a subtree begin‐
ning at either the /config/lookupd or the /locations/lookupd directory.
/config/lookupd is checked first, and /locations/lookupd is checked if
/config/lookupd does not exist. /locations/lookupd may contain global
settings, stored as values for various keys. Configuration options for
specific categories reside in the directories:
/locations/lookupd/users
/locations/lookupd/groups
/locations/lookupd/hosts
/locations/lookupd/networks
/locations/lookupd/services
/locations/lookupd/protocols
/locations/lookupd/rpcs
/locations/lookupd/mounts
/locations/lookupd/printers
/locations/lookupd/bootparams
/locations/lookupd/bootp
/locations/lookupd/aliases
/locations/lookupd/netgroups
There may also be configuration directories for each agent. These must
be subdirectories of the /locations/lookupd/agents directory:
/locations/lookupd/agents/CacheAgent
/locations/lookupd/agents/DNSAgent
/locations/lookupd/agents/FFAgent
/locations/lookupd/agents/NIAgent
/locations/lookupd/agents/NILAgent
/locations/lookupd/agents/NISAgent
Each of these agent-specific directories may have category specific sub‐
directories, for example:
/locations/locations/agents/NIAgent/printers
/locations/locations/agents/NIAgent/hosts
...
CONFIGURATION KEYS
If configuration parameters are stored in a file, each line of the file
will be of the form:
key value [value ...]
Lines beginning with “#” are treated as comments.
Configuration directories in NetInfo have property keys and values as
specified below.
Keys and permissible values for the main (global) lookupd configuration
directory or file are shown in the following table. keys and values that
apply to specific agents are described in the AGENTS section.
LogFile
Name of a log file that contains a copy of all messages sent to sys‐
log. There is no default (i.e. no log file is kept).
LogPriority
Sets the maximum priority that will be logged. Note that syslog's
highest priority (LOG_EMERG) is 0, with priority 7 being the lowest
priority (LOG_DEBUG). The default is LOG_NOTICE, meaning that only
messages of LOG_NOTICE or higher priority will be logged. This value
can also be set on the command line using the -l priority option.
StatisticsEnabled
If given the value YES, this setting will enable statistics-gather‐
ing. These statistics can then be fetched by calling lookupd with
the -statistics command line option. Details on these statistics are
found in the PERFORMANCE TUNING AND TROUBLESHOOTING section. The
default value is NO, unless lookupd is run in debug mode with the -d
or -D options.
Debug
If given the value YES, statistics gathering is enabled, and the Log‐
Priority is set to LOG_DEBUG.
MaxThreads
Maximum number of threads in the query dispatcher. The default is
64. Under moderatly heavy load, only 5 or 6 threads are used, so 64
is usually more than enough.
MaxIdleThreads
When a thread finishes servicing a query, it will usually go back to
the message queue to wait for another query. This setting limits the
maximum number of idle threads waiting on the queue. If a thread
finishes servicing a query and MaxIdleThreads are already waiting on
the queue, the thread will exit. The default value is 2.
MaxIdleServers
The dispatcher uses a server object to actually answer a client
lookup. One server is required for each active thread. The dis‐
patcher keeps a pool of servers so that they can be re-used. This
setting limits the maximum number of servers in the pool, waiting for
a query to answer. The default value is 4.
ValidateCache
This boolean value determines whether cache validation is enabled for
all cache categories. The default is YES. Use NO to disable valida‐
tion. The setting of this value may be over-ridden for specific
cache categories (see below).
ValidationLatency
If Cache validation is enabled, this integer value specifies the num‐
ber of seconds that may elapse between successive validation checks
for a particular agent. The default is 15 seconds. This value
applies to specific agents rather than to the cache. The setting of
this value may be over-ridden for specific agents (see below).
CacheCapacity
Maximum number of objects in the cache for each category (e.g. this
many users, this many hosts, ...). Least-recently-used objects are
removed when space is required. By default, there is no limit to the
cache size.
TimeToLive
Time to live (measured in seconds) in cache. The default is 43200
seconds (12 hours). This is the default mechanism used to limit the
growth of the cache.
LookupOrder
Sets the lookup order for all categories, although you may override
this for specific categories. This key takes multiple values. The
default for most categories is CacheAgent, NIAgent, and then DSAgent.
For hosts and networks, the default lookup order is CacheAgent, FFA‐
gent, DNSAgent, NIAgent, then DSAgent. For services, protocols, and
rpc, the default order is CacheAgent, FFAgent, NIAgent, then DSAgent.
Details about specifying agents in a lookup order may be found in the
AGENTS section.
Timeout
Time to wait for a response from a server. The default value is 30
seconds. Note that this timeout applies individually to all agents.
It is not a global timeout for any lookupd query. The total time
that might be taken for a single query to lookupd depends on how many
agents are involved in the lookup order for that category of item.
Options that can be set per lookup category are ValidateCache,
CacheCapacity, TimeToLive, and LookupOrder.
AGENTS
As described above, agents are specified as values of a LookupOrder con‐
figuration key. As a convenience, agent names may be shortened by omit‐
ting the trailing string “Agent” from their name. Thus, for example, DNS
may be used in place of DNSAgent.
An optional starting argument may be provided to an agent following a
colon character. For example, to use a Flat File agent that reads from
files in the directory /var/db/files rather than from files in /etc, you
could specify:
FF:/var/db/files
This mechanism allows you to specify several agents of the same type,
each with a different starting argument. For example, several Flat File
agents reading from different directories, or several DNS agents using
different domains. Starting options are described for each agent in the
sections below.
CacheAgent
The operation and configuration of the cache agent are described in
detail in the sections above. The configuration options for the Cache
agent are ValidateCache, CacheCapacity, and TimeToLive. These options may
be set globally and/or for specific categories. Options set for a spe‐
cific category will over-ride the global setting.
Note that CacheAgent should always appear first in a LookupOrder specifi‐
cation to allow lookupd to find cached entries before searching other
information services.
CacheAgent does not support a startup argument (as described at the
beginning of this section).
NIAgent
NIAgent is the NetInfo client. It supports the Timeout, ConnectTimeout,
ValidationLatency and DomainOrder options.
The Timeout option specifies a NetInfo read timeout in seconds. This
timeout is applied to all NetInfo lookups.
ConnectTimeout controls timeouts on initial NetInfo connections done at
startup time, and applies to all domains other than the local domain.
The default value is 300 seconds. A zero value indicates an unlimited
timeout.
ValidationLatency is described above in the section. NIAgent validates
cached entries by checking the NetInfo server's database checksum. The
NetInfo checksum changes whenever the database changes. Thus, any time a
NetInfo domain is updated, all cached entries from that domain will be
invalidated.
The DomainOrder option was the original mechanism implemented to allow
you to specify a list of NetInfo domains (or specific NetInfo servers)
that should be queried for information. A search order may now be speci‐
fied by using the startup argument (see below). However, the DomainOrder
option is still supported for backward compatibility.
By default, the NetInfo agent starts with a computer's local domain, then
climbs the NetInfo hierarchy until reaching the root domain. In very
rare cases, you might find that you can solve a difficult network admin‐
istration problem by altering the default lookup order. Using this
option can make your information systems configuration very confusing and
spaghetti-like, so exercise great caution in its use!
The domain search order may be set globally (for all categories of
lookups), and/or for specific categories. A domain order for a specific
category will over-ride the global order for for lookups of that type
(e.g. for user lookups).
The DomainOrder option may have multiple values. Each value specifies a
domain or a specific NetInfo server. Domain names may be absolute paths
starting at the root domain (e.g. /sales, /sol/jupiter), or a path rela‐
tive to the local domain (e.g. ../zippy, ../../marketing). A “.” stands
for the local domain. You may also specify a domain relative to a remote
computer by using a value of the form
nidomain:path@address
or
path@address
For example, If you used the value
nidomain:/central@192.42.172.1
NIAgent would connect to the computer with Internet address 192.42.172.1
and locate the domain named /central relative to that computer.
You can also include values of the form
niserver:tag@address
or
tag@address
to connect to a specific NetInfo server. For example,
niserver:network@192.42.172.5
would contact the server for the database tagged network at the given
address.
You may set the DomainOrder for a particular lookup category by creating
a category-specific configuration directory (for NetInfo-based configura‐
tions) or file (for file-based configurations).
A LookupOrder may specify one or more NIAgents, each with a startup argu‐
ment. The startup argument for NIAgent is a comma separated list of
domain or server specifications. This includes the forms supported for
the DomainOrder configuration key (see above), and may also include the
string “...” which specifies that NIAgent should include all domains from
the previous one specified in the list up to the root domain of that Net‐
Info hierarchy.
As it is the case with the DomainOrder list, you should use this facility
with great care, for you can easily make the search order very confusing.
Some LookupOrder examples may help clarify the NIAgent startup argument.
" -compact -offset indent
NI:.,extra@10.0.0.17 Local domain, then “extra” at 10.0.0.17;
NI:network@192.42.172.1,... Start with “network” at the specified
address, then climb from that domain to the
root domain.
NISAgent
The NISAgent is the NIS client. The names YPAgent and YP are aliases for
the NISAgent.
The NIS domain name must be set before lookupd starts, or this agent will
not be able to connect to a server (in which case it does nothing). The
NIS domain name is usually set during system startup using the value of
the NISDOMAIN variable in the file /etc/hostconfig. For example:
NISDOMAIN=quinta
NISAgent supports the Timeout and ValidationLatency configuration
options. NISAgent validates entries by checking the map order numbers.
Note that lookupd has separate agents for the Flat Files (see FFAgent
below) and NIS. NIS and the files are viewed as independent information
systems. You may use either agent or both in any order.
NISAgent reads the following maps. Note that some of these maps are
extensions to the standard set of maps created by most YP servers.
ethers.byaddr Host names keyed by Ethernet address
bootptab.byaddr Bootp data keyed by Ethernet address
mail.aliases E-mail aliases and distribution lists
passwd.byname Users
passwd.byuid Users
group.byname Groups
group.bygid Groups
hosts.byname Hosts
hosts.byaddr Hosts
networks.byname Networks
networks.byaddr Networks
services.byname TCP/IP service ports and protocols
protocol.byname IP Protocols
protocol.bynumber IP Protocols
rpc.byname ONC RPC programs
rpc.bynumber ONC RPC programs
mounts.byname Mounts (fstab entries) keyed by name (fspec)
printcap.byname Printers (printcap entries) keyed by name
bootparams.byname Bootparams entries keyed by name
bootp.byip Bootp entries keyed by IP address
netgroup Netgroups
NISAgent does not support a startup argument.
DNSAgent
DNSAgent is the DNS client. Cached DNS entries are validated simply by
the time-to-live associated with the DNS records. DNSAgent is only used
for host name/address and network name/address resolution.
The Mac OS X DNS library used by the DNS agent allows the system to have
a number of separate DNS clients. Each DNS client has the address of one
or more DNS servers (which the client regards as being equivalent).
Please refer to the resolver(5) man page for details on the Mac OS X DNS
resolver.
FFAgent
The FFAgent reads the “Flat Files” in your computer's /etc directory.
Specifically, it reads the files:
/etc/master.passwd Users
/etc/group Groups
/etc/hosts Computer names and addresses
/etc/networks Network names and addresses
/etc/services TCP/IP service ports and protocols
/etc/protocols IP protocol names and numbers
/etc/rpcs ONC RPC servers
/etc/fstab NFS mounts
/etc/printcap Printers
/etc/bootparams Bootparams settings
/etc/bootp Bootp settings
/etc/aliases E-mail aliases and distribution lists
/etc/netgroup Netgroups
FFAgent supports a directory path as an optional startup argument, which
is used in place of /etc.
DSAgent
The DSAgent re-directs queries to Mac OS X's Directory Services system.
See the on-line Help for the Directory Access application for more infor‐
mation on managing Directory Services.
DSAgent uses a 300 second timer for validating cached entries. Records
fetched using DSAgent are considered valid in for this period of time.
NILAgent
The NILAgent always returns a result for a query, so it stops any search.
However, it returns a negative record, which carries the meaning that the
item requested does not exist. The use of negative entries in a cache is
controversial, so lookupd does not include the NILAgent in its default
lookup order. However, adding NILAgent at the end of the LookupOrder can
result in significant performance improvements in some cases. If there
are many network information sources being searched it can take a long
time for lookupd to check them all when you ask for something that
doesn't exist. By including NILAgent at the end of the lookup order,
lookup will cache a negative record. The next time lookupd gets a
request for the same item, it will find the negative record in the cache,
and avoid a long and useless search.
It is always possible that lookupd may fail to find an item (and cache a
negative record created by NILAgent) just before someone adds that item
to one of your information systems. In that case the negative record
will be incorrect, and should be removed from cache. Unfortunately,
there's no way for lookupd to know that without doing another potentially
expensive search. As a compromise, negative records only remain in the
cache for a short time. The NILAgent assigns all negative records a
time-to-live value of 60 seconds. You may change this by setting the
TimeToLive option for the NILAgent.
NILAgent does not support a startup argument.
CONFIGURATION EXAMPLES
Here's a sample configuration as it might appear in the output of the
“nidump” utility program.
# nidump -r /locations/lookupd
name = lookupd;
LogFile = /var/log/lookupd.log;
LookupOrder = (CacheAgent, NIAgent);
CHILDREN = ({
name = users;
LookupOrder = (CacheAgent, NIAgent, FFAgent);
}, {
name = hosts;
LookupOrder = (CacheAgent, NIAgent, DNSAgent, NILAgent);
ValidateCache = NO;
}, {
name = netgroups;
LookupOrder = (CacheAgent, NIAgent, NISAgent);
}, {
name = agents;
CHILDREN = ({
name = NIAgent;
ValidationLatency = 60;
}, {
name = NILAgent;
TimeToLive = 120;
});
});
PERFORMANCE TUNING AND TROUBLESHOOTING
Simple queries can be sent to lookupd from the command line using:
lookupd-q category [[-a key [value ...]] ...]
The category may be user, group, host, network, service, protocol, rpc,
mount, printer, bootparam, bootp, alias, or netgroup. The call will
search for an item of the specified category having the given value(s)
for the specified key(s). If no key or value options are specified, the
call will return a list of all items of the specified category.
If a key is specified with no value arguments, the call will only return
items that have the specified key, regardless of its values.
If statistics are enabled (see the setting of the StatisticsEnabled key
in the CONFIGURATION section above), then statistics from lookupd can be
obtained using:
lookupd-statistics
This will print version and build information, as well as a summary of
calls and time usage. Statistics are given for each information system,
for each query, and for each query within each information system. For
example:
Cache: 1676 1153 24285
Cache all group: 3 0 18
Cache all mount: 2 0 850
Cache group gid: 434 391 22
Cache group name: 12 10 342
Cache host ip_address: 5 3 0
Cache host name: 129 52 0
...
netgroup name: 1 1 6867
network address: 4 4 3565
service name: 85 85 3964
total: 1676 1676 212371
user name: 74 74 11641
user number: 3 3 773
user uid: 760 760 45271
The first number printed in each line is the total number of calls. The
second is the number of calls answered successfully. The third is the
total time (in milliseconds) used for that item. Note that the time
required for cache validation is included in the statistics for calls to
the cache.
The command:
lookupd-flushcache
causes lookupd to empty the cache.
lookupd may be run in an interactive mode useful for testing and trou‐
bleshooting configuration problems. Since some directory information may
only be available to privileged processes, lookupd should be run as the
user root in interactive mode.
When you use the interactive mode, you start a second copy of the lookupd
program from a command line with a -d option:
mycomputer# lookupd-d
lookupd version 123
Enter command name, "help", or "quit" to exit
>
This second copy of lookupd runs independently of the system's “main”
lookupd and does not provide information to other programs running on
your system. This allows you to try queries and test configuration
options without disturbing normal operations. The second copy of lookupd
will attempt to read its configuration options from a NetInfo directory
named /locations/lookupd_debug (NetInfo) or /etc/lookupd_debug (files).
If they don't exist, it will try /locations/lookupd or /etc/lookupd.
The interactive mode command line supports escape completion for com‐
mands, so you can type a character or two then press the Escape key.
lookupd will complete as much of the command as it can (sometimes there
are several command that start with the same characters). To see all
possible completions, press Control-d. To see all possible commands,
press Control-d before you type in any characters at all. For on-line
help, use the “help” command.
> help
Enter command name, "help" for general help, or "quit" to exit help
help> help
This is lookupd's interactive query and testing facility.
...
There are interactive commands for all standard queries, such as user‐
WithName, hostWithInternetAddress, and so on. When you enter a query,
lookupd will print the result that it located or “nil” if the item was
not found. lookupd also keeps track of the information source for each
item and a number of other useful pieces of information that can help you
track internal activities. For example:
> userWithName: jru
Dictionary: "NIAgent: user jru"
_lookup_NI_checksum: 68850661
_lookup_NI_domain: /
_lookup_NI_index: 2
_lookup_NI_server: pacific/network
_lookup_info_system: NetInfo
_writers_passwd: jru
change: 0
expire: 0
gid: 114
home: /Network/Servers/fiji/Users/jru
name: jru
netgroups: programmer
passwd: 2YEsFfX2fmC8.
realname: Jane Random User
shell: /bin/csh
uid: 1664
+ Category: user
+ Time to live: 43200
+ Age: 0 (expires in 43200 seconds)
+ Negative: No
+ Cache hits: 3
+ Retain count: 6
When you enter a query, lookupd follows its normal lookup order to obtain
an answer. If you wish to query a specific agent, you can use the agent
command. This stops the normal lookup and will direct all further
queries to the agent you specify. You can use the agent command again to
switch to a different agent, or use the normalLookupOrder command to
resume normal lookups.
> agent: NI
> hostWithName: fiji
Dictionary: "NIAgent: host fiji"
_lookup_NI_checksum: 68850661
_lookup_NI_domain: /
_lookup_NI_index: 1
_lookup_NI_server: pacific/network
_lookup_info_system: NetInfo
bootfile: mach
bootparams:
en_address: 0:5:2:fe:ef:4b
ip_address: 192.42.172.168
name: fiji
netgroups: island
serves: fiji/local
> agent: DNS
> hostWithName: fiji
Dictionary: "D-0x6d470"
_lookup_DNS_time_to_live: 28800
_lookup_DNS_timestamp: 912796168
_lookup_domain: mydomain.com
_lookup_info_system: DNS
ip_address: 192.42.172.168
name: fiji.mydomain.com fiji
> normalLookupOrder
Using normal lookup order
You can get timing and usage statistics for all types of lookups using
the statistics command. Timing measurements can help you determine what
might be causing slowdowns or problems on your network.
You can examine all items in memory using the memory and showMemoryObject
commands. This includes stored configuration settings, statistical
records, and cached information.
OPEN SOURCE
The source code for lookupd is a available as part of Apple's Darwin open
source initiative. lookupd is part of the netinfo project. More infor‐
mation on Darwin may be found on the Web at
http://www.publicsource.apple.com
The netinfo project sources include a script named “BUILD” that may be
used to compile the sources.
FILES
/var/run/lookupd.pid, /etc/lookupd
SEE ALSOnetinfod(8), mach_init(8), syslog(5)Mac OS May 22, 2000 Mac OS
