import of dnsmasq-2.46.tar.gz

man/dnsmasq.8

@@ -385,6 +385,14 @@ Return a PTR DNS record.
 .B --naptr-record=<name>,<order>,<preference>,<flags>,<service>,<regexp>[,<replacement>]
 Return an NAPTR DNS record, as specified in RFC3403.
 .TP
+.B --cname=<cname>,<target>
+Return a CNAME record which indicates that <cname> is really
+<target>. There are significant limitations on the target; it must be a
+DNS name which is known to dnsmasq from /etc/hosts (or additional
+hosts files) or from DHCP. If the target does not satisfy this
+criteria, the whole cname is ignored. The cname must be unique, but it
+is permissable to have more than one cname pointing to the same target.
+.TP
 .B --interface-name=<name>,<interface>
 Return a DNS record associating the name with the primary address on
 the given interface. This flag specifies an A record for the given
@@ -465,9 +473,11 @@ hardware addresses to identify hosts by prefixing with 'id:'. Thus:
 refers to the host with client identifier 01:02:03:04. It is also
 allowed to specify the client ID as text, like this:
 .B --dhcp-host=id:clientidastext,..... 
+
 The special option id:* means "ignore any client-id 
 and use MAC addresses only." This is useful when a client presents a client-id sometimes 
 but not others.
+
 If a name appears in /etc/hosts, the associated address can be
 allocated to a DHCP lease, but only if a 
 .B --dhcp-host
@@ -478,8 +488,10 @@ instance
 .B --dhcp-host=00:20:e0:3b:13:af,ignore
 This is
 useful when there is another DHCP server on the network which should
-be used by some machines. The net:<network-id> sets the network-id tag
-whenever this dhcp-host directive is in use.This can be used to 
+be used by some machines.
+
+The net:<network-id> sets the network-id tag
+whenever this dhcp-host directive is in use. This can be used to 
 selectively send DHCP options just for this host. When a host matches any
 dhcp-host directive (or one implied by /etc/ethers) then the special
 network-id tag "known" is set. This allows dnsmasq to be configured to
@@ -490,13 +502,25 @@ wildcard bytes, so for example
 .B --dhcp-host=00:20:e0:3b:13:*,ignore 
 will cause dnsmasq to ignore a range of hardware addresses. Note that
 the "*" will need to be escaped or quoted on a command line, but not
-in the configuration file. Hardware addresses normally match any
+in the configuration file.
+
+Hardware addresses normally match any
 network (ARP) type, but it is possible to restrict them to a single
 ARP type by preceding them with the ARP-type (in HEX) and "-". so 
 .B --dhcp-host=06-00:20:e0:3b:13:af,1.2.3.4 
 will only match a
 Token-Ring hardware address, since the ARP-address type for token ring
-is 6.
+is 6. 
+
+As a special case, it is possible to include more than one
+hardware address. This allows an IP address to be associated with
+multiple hardware addresses, and gives dnsmasq permission to abandon a
+DHCP lease to one of the hardware addresses when another one asks for
+a lease. Beware that this is a dangerous thing to do, it will only
+work reliably if only one of the hardware addresses is active at any
+time and there is no way for dnsmasq to enforce this. It is, however
+useful, for instance to allocate a stable IP address to a laptop which
+has both wired and wireless interfaces.
 .TP
 .B --dhcp-hostsfile=<file>
 Read DHCP host information from the specified file. The file contains 
@@ -693,11 +717,13 @@ port number is used for the server and the port number plus one used
 for the client. Finally, two port numbers allows arbitrary
 specification of both server and client ports for DHCP.
 .TP
-.B \-3, --bootp-dynamic
+.B \-3, --bootp-dynamic[=<network-id>[,<network-id>]]
 Enable dynamic allocation of IP addresses to BOOTP clients. Use this
 with care, since each address allocated to a BOOTP client is leased
 forever, and therefore becomes permanently unavailable for re-use by
-other hosts.
+other hosts. if this is given without tags, then it unconditionally
+enables dynamic allocation. With tags, only when the tags are all
+set. It may be repeated with different tag sets. 
 .TP
 .B \-5, --no-ping
 By default, the DHCP server will attempt to ensure that an address in
@@ -723,18 +749,22 @@ removed in a future release.
 .TP 
 .B \-6 --dhcp-script=<path>
 Whenever a new DHCP lease is created, or an old one destroyed, the
-binary specified by this option is run. The arguments to the process
+executable specified by this option is run. The arguments to the process
 are "add", "old" or "del", the MAC
-address of the host (or "<null>"), the IP address, and the hostname,
+address of the host, the IP address, and the hostname,
 if known. "add" means a lease has been created, "del" means it has
 been destroyed, "old" is a notification of an existing lease when
 dnsmasq starts or a change to MAC address or hostname of an existing
 lease (also, lease length or expiry and client-id, if leasefile-ro is set).
-The process is run as root (assuming that dnsmasq was originally run as
+If the MAC address is from a network type other than ethernet,
+it will have the network type prepended, eg "06-01:23:45:67:89:ab" for
+token ring. The process is run as root (assuming that dnsmasq was originally run as
 root) even if dnsmasq is configured to change UID to an unprivileged user.
 The environment is inherited from the invoker of dnsmasq, and if the
 host provided a client-id, this is stored in the environment variable
-DNSMASQ_CLIENT_ID. If the client provides vendor-class or user-class 
+DNSMASQ_CLIENT_ID. If the fully-qualified domain name of the host is
+known, the domain part is stored in DNSMASQ_DOMAIN. 
+If the client provides vendor-class or user-class 
 information, these are provided in DNSMASQ_VENDOR_CLASS and 
 DNSMASQ_USER_CLASS0..DNSMASQ_USER_CLASSn variables, but only for
 "add" actions or "old" actions when a host resumes an existing lease,
@@ -785,8 +815,9 @@ as if they had arrived at <interface>. This option is only available
 on BSD platforms, and is necessary when using "old style" bridging, since
 packets arrive at tap interfaces which don't have an IP address.
 .TP
-.B \-s, --domain=<domain>
-Specifies the domain for the DHCP server. This has two effects;
+.B \-s, --domain=<domain>[,<address range>]
+Specifies DNS domains for the DHCP server. Domains may be be given 
+unconditionally (without the IP range) or for limited IP ranges. This has two effects;
 firstly it causes the DHCP server to return the domain to any hosts
 which request it, and secondly it sets the domain which it is legal
 for DHCP-configured hosts to claim. The intention is to constrain
@@ -803,7 +834,28 @@ and have a machine whose DHCP hostname is "laptop". The IP address for that mach
 .B dnsmasq
 both as "laptop" and "laptop.thekelleys.org.uk". If the domain is
 given as "#" then the domain is read from the first "search" directive
-in /etc/resolv.conf (or equivalent). 
+in /etc/resolv.conf (or equivalent). The address range can be of the form
+<ip address>,<ip address> or <ip address>/<netmask> or just a single
+<ip address>. See 
+.B --dhcp-fqdn
+which can change the behaviour of dnsmasq with domains.
+.TP
+.B --dhcp-fqdn
+In the default mode, dnsmasq inserts the unqualified names of
+DHCP clients into the DNS. For this reason, the names must be unique,
+even if two clients which have the same name are in different
+domains. If a second DHCP client appears which has the same name as an
+existing client, the name is transfered to the new client. If 
+.B --dhcp-fqdn
+is set, this behaviour changes: the unqualified name is no longer
+put in the DNS, only the qualified name. Two DHCP clients with the
+same name may both keep the name, provided that the domain part is
+different (ie the fully qualified names differ.) To ensure that all
+names have a domain part, there must be at least 
+.B --domain 
+without an address specified when 
+.B --dhcp-fqdn 
+is set.
 .TP
 .B --enable-tftp
 Enable the TFTP server function. This is deliberately limited to that
@@ -1006,6 +1058,9 @@ collects a set of valid network-id tags, one from the
 .B dhcp-range
 used to allocate the address, one from any matching 
 .B dhcp-host
+(and "known" if a dhcp-host matches) 
+the tag "bootp" for BOOTP requests, a tag whose name is the 
+name if the interface on which the request arrived,
 and possibly many from matching vendor classes and user
 classes sent by the DHCP client. Any 
 .B dhcp-option