1DHCPCD-RUN-HOOKS(8) BSD System Manager's Manual DHCPCD-RUN-HOOKS(8)
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4 dhcpcd-run-hooks — DHCP client configuration script
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7 dhcpcd-run-hooks is used by dhcpcd(8) to run any system and user defined
8 hook scripts. System hook scripts are found in /usr/libexec/dhcpcd-hooks
9 and the user defined hooks are /etc/dhcpcd.enter-hook. and
10 /etc/dhcpcd.exit-hook. The default install supplies hook scripts for
11 configuring /etc/resolv.conf and the hostname. Your distribution may
12 have included other hook scripts to say configure ntp or ypbind. A test
13 hook is also supplied that simply echos the dhcp variables to the console
14 from DISCOVER message.
15 The hooks scripts are loaded into the current shell rather than executed
17 in their own process. This allows each hook script, such as
18 /etc/dhcpcd.enter-hook to customise environment variables or provide al‐
19 ternative functions to hooks further down the chain. As such, using the
20 shell builtins exit, exec or similar will cause dhcpcd-run-hooks to exit
21 at that point.
22 Each time dhcpcd-run-hooks is invoked, $interface is set to the interface
24 that dhcpcd is run on and $reason is to the reason why q dhcpcd-run-hooks
25 was invoked. DHCP information to be configured is held in variables
26 starting with the word new_ and old DHCP information to be removed is
27 held in variables starting with the word old_. dhcpcd can display the
28 full list of variables it knows how about by using the -V, --variables
29 argument.
30 Here's a list of reasons why dhcpcd-run-hooks could be invoked:
32 PREINIT dhcpcd is starting up and any pre-initialisation should
34 be done.
35 CARRIER dhcpcd has detected the carrier is up. This is gener‐
37 ally just a notification and no action need be taken.
38 NOCARRIER dhcpcd lost the carrier. The cable may have been un‐
40 plugged or association to the wireless point lost.
41 NOCARRIER_ROAMING
43 dhcpcd lost the carrier but the interface configuration
44 is persisted. The OS has to support wireless roaming
45 or IP Persistance for this to happen.
46 INFORM | INFORM6 dhcpcd informed a DHCP server about its address and ob‐
48 tained other configuration details.
49 BOUND | BOUND6 dhcpcd obtained a new lease from a DHCP server.
51 RENEW | RENEW6 dhcpcd renewed it's lease.
53 REBIND | REBIND6 dhcpcd has rebound to a new DHCP server.
55 REBOOT | REBOOT6 dhcpcd successfully requested a lease from a DHCP
57 server.
58 DELEGATED6 dhcpcd assigned a delegated prefix to the interface.
60 IPV4LL dhcpcd obtained an IPV4LL address, or one was removed.
62 STATIC dhcpcd has been configured with a static configuration
64 which has not been obtained from a DHCP server.
65 3RDPARTY dhcpcd is monitoring the interface for a 3rd party to
67 give it an IP address.
68 TIMEOUT dhcpcd failed to contact any DHCP servers but was able
70 to use an old lease.
71 EXPIRE | EXPIRE6 dhcpcd's lease or state expired and it failed to obtain
73 a new one.
74 NAK dhcpcd received a NAK from the DHCP server. This
76 should be treated as EXPIRE.
77 RECONFIGURE dhcpcd has been instructed to reconfigure an interface.
79 ROUTERADVERT dhcpcd has received an IPv6 Router Advertisement, or
81 one has expired.
82 STOP | STOP6 dhcpcd stopped running on the interface.
84 STOPPED dhcpcd has stopped entirely.
86 DEPARTED The interface has been removed.
88 FAIL dhcpcd failed to operate on the interface. This nor‐
90 mally happens when dhcpcd does not support the raw in‐
91 terface, which means it cannot work as a DHCP or Zero‐
92 Conf client. Static configuration and DHCP INFORM is
93 still allowed.
94 TEST dhcpcd received an OFFER from a DHCP server but will
96 not configure the interface. This is primarily used to
97 test the variables are filled correctly for the script
98 to process them.
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101 dhcpcd will clear the environment variables aside from $PATH. The fol‐
102 lowing variables will then be set, along with any protocol supplied ones.
103 $interface the name of the interface.
105 $protocol the protocol that triggered the event.
107 $reason as described above.
109 $pid the pid of dhcpcd.
111 $ifcarrier the link status of $interface: unknown, up
113 or down.
114 $ifmetric $interface preference, lower is better.
116 $ifwireless 1 if $interface is wireless, otherwise 0.
118 $ifflags $interface flags.
120 $ifmtu $interface MTU.
122 $ifssid the name of the SSID the interface is con‐
124 nected to.
125 $interface_order A list of interfaces, in order of prefer‐
127 ence.
128 $if_up true if the interface is up, otherwise
130 false. This is more than IFF_UP and may not
131 be equal.
132 $if_down true if the interface is down, otherwise
134 false. This is more than IFF_UP and may not
135 be equal.
136 $af_waiting Address family waiting for, as defined in
138 dhcpcd.conf(5).
139 $profile the name of the profile selected from
141 dhcpcd.conf(5).
142 $new_delegated_dhcp6_prefix space separated list of delegated prefixes.
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146 When dhcpcd-run-hooks runs, it loads /etc/dhcpcd.enter-hook and any
147 scripts found in /usr/libexec/dhcpcd-hooks in a lexical order and then
148 finally /etc/dhcpcd.exit-hook
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151 dhcpcd(8)
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154 Roy Marples <roy@marples.name>
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157 Please report them to http://roy.marples.name/projects/dhcpcd
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160 dhcpcd will validate the content of each option against its encoding.
161 For string, ascii, raw or binhex encoding it's up to the user to validate
162 it for the intended purpose.
163 When used in a shell script, each variable must be quoted correctly.
165BSD December 27, 2020 BSD