1kresd(8) Knot Resolver 4.3.0 kresd(8)
2
6 kresd - full caching DNSSEC-enabled Knot Resolver 4.3.0.
7
9 kresd [-a|--addr addr[@port]] [-t|--tls addr[@port]] [-S|--fd fd]
10 [-T|--tlsfd fd] [-c|--config config] [-f|--forks N] [-q|--quiet]
11 [-v|--verbose] [-V|--version] [-h|--help] [rundir]
12
14 Knot Resolver is a DNSSEC-enabled full caching resolver.
15 Default mode of operation: when it receives a DNS query it iteratively
17 asks authoritative nameservers starting from root zone (.) and ending
18 with a nameservers authoritative for queried name. Automatic DNSSEC
19 means verification of integrity of authoritative responses by following
20 keys and signatures starting from root. Root trust anchor is automati‐
21 cally bootstrapped from IANA, or you can provide a file with root trust
22 anchors (same format as Unbound or BIND9 root keys file).
23 The daemon also caches intermediate answers into cache, which by
25 default uses LMDB memory-mapped database. This has a significant advan‐
26 tage over in-memory caches as the process may be stopped and restarted
27 without loss of cache entries. In multi-user scenario a shared cache is
28 potential privacy/security issue, with kresd each user can have
29 resolver cache in their private directory and use it in similar fashion
30 to keychain.
31 By default, no configuration is needed, only a directory where the dae‐
33 mon can store runtime data (cache, control sockets, ...)
34 To use a locally running kresd for resolving put
36 nameserver 127.0.0.1
38 into resolv.conf(5) and start kresd
40 $ kresd -a 127.0.0.1
42 [system] interactive mode
43 >
44 The daemon may be configured also as a plain forwarder using query
46 policies, that requires creating a file config in daemon runtime direc‐
47 tory. See daemon/README.md for more information about interacting with
48 CLI and configuration file options, or visit https://knot-
49 resolver.readthedocs.io online documentation.
50 # Create a basic forwarder configuration
52 $ cat << EOF > config
53 modules = { 'policy' }
54 policy.add(policy.all(policy.FORWARD('192.168.1.1')))
55 $ kresd -a 127.0.0.1
56 EOF
57 The available CLI options are:
59 -a addr[@port], --addr=<addr[@port]>
61 Listen on given address (and port) pair. If no port is given, 53
62 is used as a default. Option may be passed multiple times to
63 listen on more addresses.
64 -t addr[@port], --tls=<addr[@port]>
66 Listen using TLS on given address (and port) pair. If no port is
67 given, 853 is used as a default. Option may be passed multiple
68 times to listen on more addresses.
69 -S fd, --fd=<fd>
71 Listen on given file descriptor(s), passed by supervisor.
72 Option may be passed multiple times to listen on more file
73 descriptors.
74 -T fd, --tlsfd=<fd>
76 Listen using TLS on given file descriptor(s), passed by supervi‐
77 sor. Option may be passed multiple times to listen on more file
78 descriptors.
79 -c config, --config=<config>
81 Set the config file with settings for kresd to read instead of
82 reading the file at the default location (config). The syntax is
83 described in daemon/README.md.
84 -f N, --forks=<N>
86 With this option, the daemon is started in non-interactive mode
87 and instead creates a UNIX socket in rundir that the operator
88 can connect to for interactive session. A number greater than 1
89 forks the daemon N times, all forks will bind to same addresses
90 and the kernel will load-balance between them on Linux with
91 SO_REUSEPORT support.
92 When socket-activated and supervised by systemd or the equiva‐
94 lent, kresd defaults to --forks=1, and must not be set to any
95 other value. If you want multiple concurrent processes super‐
96 vised in this way, they should be supervised independently (see
97 kresd.systemd(7)).
98 -q, --quiet
100 Daemon will refrain from printing the command prompt.
101 -v, --verbose
103 Increase verbosity. If given multiple times, more information is
104 logged. This is in addition to the verbosity (if any) from the
105 config file.
106 -h Show short commandline option help.
108 -V Show the version.
110
112 kresd.systemd(7), https://knot-resolver.readthedocs.io/en/v4.3.0/
113
115 kresd developers are mentioned in the AUTHORS file in the distribution.
116CZ.NIC 2019-12-04 kresd(8)