.TH NDB 8 .SH NAME query, mkhash, mkdb, cs, csquery, dns, dnsquery, ipquery, dnsdebug, mkhosts \- network database .SH SYNOPSIS .B ndb/query [ .B -f .I dbfile ] .I "attr value" [ .I rattr ] .br .B ndb/ipquery .I "attr value" .I rattr... .br .B ndb/mkhash .I "file attr" .br .B ndb/cs [ .B -n ] [ .B -f .I dbfile ] [ .B -x .I netmtpt ] .br .B ndb/csquery [ .B -s ] [ .B server [ .I addr... ] ] .br .B ndb/dns [ .B -rsn ] [ .B -f .I dbfile ] [ .B -x .I netmtpt ] [ .B -z .I program ] .br .B ndb/dnsquery .br .B ndb/dnsdebug [ .B -rx ] [ [ .BI @ server ] .I domain-name [ .I type ] ] .br .B ndb/mkdb .SH DESCRIPTION The network database holds administrative information used by network programs such as .IR dhcpd (8), .IR ipconfig (8), .IR con (1), etc. .PP .I Ndb/query searches the database for an attribute of type .I attr and value .IR value . If .I rattr is not specified, all entries matched by the search are returned. If .I rattr is specified, the value of the first pair with attribute .I rattr of all the matched entries is returned. .PP .I Ndb/ipquery uses .I ndbipinfo (see .IR ndb (2)) to search for the values of the attributes .I rattr corresponding to the system with entries of attribute type .I attr and value .IR value . .PP .I Ndb/mkhash creates a hash file for all entries with attribute .I attr in database file .IR file . The hash files are used by .I ndb/query and by the ndb library routines. .PP .I Ndb/cs is a server used by .IR dial (2) to translate network names. It is started at boot time. It finds out what networks are configured by looking for .B /net/*/clone when it starts. It can also be told about networks by writing to .B /net/cs a message of the form: .IP .B "add net1 net2 ..." .PP .I Ndb/cs also sets the system name in .B /dev/sysname if it can figure it out. The options are: .TP .B -f supplies the name of the data base file to use, default .BR /lib/ndb/local . .TP .B -x specifies the mount point of the network. .TP .B -n causes cs to do nothing but set the system name. .PP .I Ndb/csquery can be used to query .I ndb/cs to see how it resolves addresses. .I Ndb/csquery prompts for addresses and prints out what .I ndb/cs returns. .I Server defaults to .BR /net/cs . If any .I addrs are specified, .I ndb/csquery prints their translations and immediately exits. The exit status will be nil only if all addresses were successfully translated The .B -s flag sets exit status without printing any results. .PP .I Ndb/dns is a server used by .I ndb/cs and by remote systems to translate Internet domain names. .I Ndb/dns is started at boot time. By default .I dns serves only requests written to .BR /net/dns . The options are: .TP .B -f supplies the name of the data base file to use, default .BR /lib/ndb/local . .TP .B -x specifies the mount point of the network. .TP .B -s also answer domain requests sent to UDP port 53. .TP .B -n whenever a zone that we serve changes, send UDP NOTIFY messages to any dns slaves for that zone. .TP .B -z whenever we receive a UDP NOTIFY message, run .I program with the domain name of the area as its argument. .TP .B -r defer to other servers to resolve queries. .PP When the .B -r option is specified, the servers used come from the .I dns attribute in the database. For example, to specify a set of dns servers that will resolve requests for systems on the network .IR mh-net : .EX ipnet=mh-net ip=135.104.0.0 ipmask=255.255.0.0 dns=ns1.cs.bell-labs.com dns=ns2.cs.bell-labs.com dom=ns1.cs.bell-labs.com ip=135.104.1.11 dom=ns2.cs.bell-labs.com ip=135.104.1.12 .EE .PP The server for a domain is indicated by a database entry containing both a .I dom and a .I ns attribute. For example, the entry for the Internet root is: .EX dom= ns=A.ROOT-SERVERS.NET ns=B.ROOT-SERVERS.NET ns=C.ROOT-SERVERS.NET dom=A.ROOT-SERVERS.NET ip=198.41.0.4 dom=B.ROOT-SERVERS.NET ip=128.9.0.107 dom=C.ROOT-SERVERS.NET ip=192.33.4.12 .EE The last three lines provide a mapping for the server names to their ip addresses. This is only a hint and will be superseded from whatever is learned from servers owning the domain. .PP You can also serve a subtree of the domain name space from the local database. You indicate subtrees that you'ld like to serve by adding an .B soa= attribute to the root entry. For example, the Bell Labs CS research domain is: .EX dom=cs.bell-labs.com soa= refresh=3600 ttl=3600 ns=plan9.bell-labs.com ns=ns1.cs.bell-labs.com ns=ns2.cs.bell-labs.com mb=presotto@plan9.bell-labs.com mx=mail.research.bell-labs.com pref=20 mx=plan9.bell-labs.com pref=10 dnsslave=nslocum.cs.bell-labs.com dnsslave=vex.cs.bell-labs.com .EE Here, the .B mb entry is the mail address of the person responsible for the domain (default .BR postmaster ). The .B mx entries list mail exchangers for the domain name and .B refresh and .B ttl define the area refresh interval and the minimum TTL for records in this domain. The .B dnsslave entries specify slave DNS servers that should be notified when the domain changes. The notification also requires the .B -n flag. .PP You can also serve reverse lookups (returning the name that goes with an IP address) by adding an .B soa= attribute to the entry defining the root of the reverse space. For example, to provide reverse lookup for all addresses in starting with 135.104 you must have a record like: .EX dom=104.135.in-addr.arpa soa= refresh=3600 ttl=3600 ns=plan9.bell-labs.com ns=ns1.cs.bell-labs.com ns=ns2.cs.bell-labs.com .EE Notice the form of the reverse address, i.e., it's the bytes of the address range you are serving reversed and with .B .in-addr.arpa appended. This is a standard form for a domain name in an IPv4 PTR record. .PP If such an entry exists in the database, reverse addresses will automaticly be generated from any IP addresses in the database that are under this root. For example .EX dom=ns1.cs.bell-labs.com ip=135.104.1.11 .EE will automaticly create both forward and reverse entries for .B ns1.cs.bell-labs.com . Unlike other DNS servers, there's no way to generate inconsistent forward and reverse entries. .PP Delegation of a further subtree to another set of name servers is indicated by an .B soa=delegated attribute. .EX dom=bignose.cs.research.bell-labs.com soa=delegated ns=anna.cs.research.bell-labs.com ns=dj.cs.research.bell-labs.com .EE Nameservers within the delegated domain (as in this example) must have their IP addresses listed elsewhere in .I ndb files. .PP Wild-carded domain names can also be used. For example, to specify a mail forwarder for all Bell Labs research systems: .EX dom=*.research.bell-labs.com mx=research.bell-labs.com .EE `Cname' aliases may be established by adding a .B cname attribute giving the real domain name; the name attached to the .B dom attribute is the alias. `Cname' aliases are severely restricted; the aliases may have no other attributes than .B dom and are daily further restricted in their use by new RFCs. .EX cname=anna.cs.research.bell-labs.com dom=www.cs.research.bell-labs.com .EE .I Ndb/dnsquery can be used to query .I ndb/dns to see how it resolves requests. .I Ndb/dnsquery prompts for commands of the form .IP .I "domain-name request-type" .LP where .I request-type can be .BR ip , .BR mx , .BR ns , .BR cname , .BR ptr .... In the case of the inverse query type, .BR ptr , .I dnsquery will reverse the ip address and tack on the .B .in-addr.arpa for you. .PP .I Ndb/dnsdebug is like .I ndb/dnsquery but bypasses the local server. It communicates via UDP with the domain name servers in the same way that the local resolver would and displays all packets received. The query can be specified on the command line or can be prompted for. The queries look like those of .I ndb/dnsquery with one addition. .I Ndb/dnsdebug can be directed to query a particular name server by the command .BI @ name-server\f1. From that point on, all queries go to that name server rather than being resolved by .IR dnsdebug . The .B @ command returns query resolution to .IR dnsdebug . Finally, any command preceded by a .BI @ name-server sets the name server only for that command. .PP Normally .I dnsdebug uses the .B /net interface and the database file .BR /lib/ndb/local. The .B -x option directs .I dnsdebug to use the .B /net.alt interface and .B /lib/ndb/external file. The .B -r option is the same as for .IR ndb/dns . .PP .I Ndb/mkdb is used in concert with .IR awk (1) scripts to convert uucp systems files and IP host files into database files. It is very specific to the situation at Murray Hill. .PP When the database files change underfoot, .I ndb/cs and .I ndb/dns track them properly. Nonetheless, to keep the database searches efficient it is necessary to run .I ndb/mkhash whenever the files are modified. It may be profitable to control this by a frequent .IR cron (8) job. .PP .I Ndb/mkhosts generates a BSD style .BR hosts , .BR hosts.txt , and .B hosts.equiv files from an ndb data base file specified on the command line (default .BR /lib/ndb/local ). For local reasons the files are called .BR hosts.1127 , .BR astro.txt , and .BR hosts.equiv . .SH EXAMPLES .EX % ndb/query sys helix sys=helix dom=helix.research.bell-labs.com bootf=/mips/9powerboot ip=135.104.117.31 ether=080069020427 proto=il % ndb/dnsquery > plan9.bell-labs.com ip plan9.bell-labs.com ip 204.178.31.2 > 204.178.31.2 ptr 2.31.178.204.in-addr.arpa ptr plan9.bell-labs.com 2.31.178.204.in-addr.arpa ptr ampl.com > .EE .SH FILES .TF /lib/ndb/local.*xxx .TP .B /lib/ndb/local first database file searched .TP .B /lib/ndb/local.* hash files for .B /lib/ndb/local .TP .B /srv/cs service file for .I ndb/cs .TP .B /net/cs where .B /srv/cs gets mounted .TP .B /srv/dns service file for .I ndb/dns .TP .B /net/dns where .B /srv/dns gets mounted .SH SOURCE .B /sys/src/cmd/ndb .SH SEE ALSO .IR ndb (2) .IR ndb (6)