Skip to Content

Changes for page Openwrt Notes

Last modified by Leon Poon on 2019/11/02 17:53
From version 38.1
edited by Leon Poon
on 2019/11/02 06:18
Change comment: There is no comment for this version
To version 1.1
edited by Leon Poon
on 2019/01/05 14:43
Change comment: There is no comment for this version

Summary

Details

Page properties
Title
... ... @@ -1,1 +1,1 @@
1 -Openwrt Notes
1 +Openwrt Boot Notes
Content
... ... @@ -6,136 +6,15 @@
6 6  
7 7  /init is a script which sets INITRAMFS=1 and then execs /sbin/init.
8 8  
9 -/sbin/init is ELF comes from procd package. What it does (as pid=1):
9 +/sbin/init is ELF comes from procd package. What it does:
10 10  
11 -* early (different from procd early):
11 +* early:
12 12  ** mount /proc, /sysfs, and create /dev nodes, create /tmp subdirs etc
13 13  ** set PATH
14 -* kmodloader in subprocess (waits until done)
14 +* kmodloader in subprocess
15 15  * preinit
16 16  ** plugd in subprocess (seem to deal with firmware)
17 17  ** /etc/preinit in subprocess
18 -* when /etc/preinit is done then it execvp the "real" /sbin/procd
18 +* when /etc/preinit is done then it execs and replaces itself with the "real" /sbin/procd
19 19  
20 -procd states:
21 -
22 -* early (first state):
23 -** coldplug (remount /dev, etc)
24 -*** start udevtrigger in subproc
25 -*** when udevtrigger completes, hotplug
26 -*** when hotplug completes, next state (ubus)
27 -* ubus:
28 -** start attempts to connect to ubs
29 -** start ubus as service
30 -** once connection's done then next state (init)
31 -* init - read /etc/inittab and run:
32 -** respawn - things that need to keep rerunning once quitted
33 -** askconsole
34 -** askfirst - the "Press Enter to activate this console" message
35 -** sysinit - (usually /etc/init.d/rcS with S) and then next state (running)
36 -* running - waits for shutdown signal (usr1/usr2) or reboot (int/term)
37 -* shutdown
38 -** runs shutdown command per inittab (also /etc/init.d/rcS but with K)
39 -** when done next state (halt)
40 -* halt - kill everything and either enter sleep loop or reboots
41 -
42 -= Modules =
43 -
44 -{{code}}
45 -cp -va ./build_dir/target-*/linux-*/linux-4*/modules.builtin ./staging_dir/target-*/root-*/lib/modules/4*
46 -# tar -C ./staging_dir/target-*/root-*/ -vcjf modules.tar.bz2 lib/modules
47 -{{code}}
48 -
49 -= Debian =
50 -
51 -{{code}}
52 -debootstrap --variant=minbase --include locales,sudo,sysvinit-core,sysvinit-utils,vim-nox,screen,wget,ntp,bridge-utils,ifupdown --exclude=nano,vim-tiny --foreign stretch $PWD
53 -chroot $PWD debootstrap/debootstrap --second-stage
54 -{{/code}}
55 -
56 -{{code}}
57 -qemu-debootstrap --include=locales,sudo,sysvinit-core,sysvinit-utils,vim-nox,screen,wget,ntp,bridge-utils,ifupdown --exclude=nano,vim-tiny,systemd,systemd-sysv --arch mipsel stretch /mnt/cdrom
58 -{{/code}}
59 -
60 -Do not install openssh-server during bootstrap otherwise it will bring in systemd!
61 -
62 -Things to do after debootstrap:
63 -
64 -* [[get rid of systemd>>http://without-systemd.org/wiki/index.php/How_to_remove_systemd_from_a_Debian_Stretch_installation]]
65 -* set hostname
66 -* set root password
67 -* /etc/network/interfaces (TODO: swconfig while still in openwrt initramfs space?)
68 -* apt-get install ~-~-no-install-recommends openssh-server (check that it is without libpam-systemd and systemd!!)
69 -* apt-get install net-tools file ntp openssh-server gcc
70 -** net-tools for ifconfig
71 -** gcc for?
72 -* echo vm.min_free_kbytes=16384 > /etc/sysctl.d/min_free_kbytes.conf
73 -* kernel modules ( tar -C ./staging_dir/target-*/root-*/ -vcjf - lib/modules | ssh TARGET_IP tar -C / -vxjf - )
74 -* read-only root
75 -
76 -Needs CONFIG_DEVTMPFS=y in kernel.
77 -
78 -{{code language="bash"}}
79 -mkdir -pv /mnt &&
80 -mknod /dev/sda b 8 0 &&
81 -cryptsetup open /dev/sda usb &&
82 -vgchange -ay vol_grp1 &&
83 -mount /dev/vol_grp1/logical_vol1 /mnt -o ro
84 -{{/code}}
85 -
86 -{{code language="bash"}}
87 -chroot /mnt /bin/bash
88 -{{/code}}
89 -
90 -{{code language="bash"}}
91 -mount proc /proc -t proc
92 -{{/code}}
93 -
94 -{{code language="bash"}}
95 -exec switch_root /mnt /sbin/init
96 -{{/code}}
97 -
98 -{{code language="bash"}}
99 -ip addr add dev eth0 IP/NM
100 -ip link set eth0 up
101 -ip route add default via GW
102 -{{/code}}
103 -
104 -= Network =
105 -
106 -{{code language="bash"}}
107 -sed -re 's/^boot_run_hook/#\0/g' -i /etc/preinit
108 -PREINIT=1 . /etc/preinit
109 -preinit_config_board # set up the switch and lan ports on eth0.2, and create ip link
110 -json_select switch
111 -json_select switch0
112 -json_add_boolean reset 0 # do not reset when setting up wan ports on eth0.1
113 -json_select ..
114 -json_select ..
115 -preinit_config_switch switch0 eth0.1 # set up wan ports
116 -preinit_ip_config eth0.1 # create ip link
117 -ip address flush dev eth0 # del default address
118 -for pi_ifname in eth0.1 eth0.2; do
119 - ip -4 address flush dev $pi_ifname # del default address
120 - ip link set dev $pi_ifname down
121 -done
122 -{{/code}}
123 -
124 -
125 -= UBI =
126 -
127 -{{code language="text"}}define Build/append-ubi
128 - sh $(TOPDIR)/scripts/ubinize-image.sh \
129 - $(if $(UBOOTENV_IN_UBI),--uboot-env) \
130 - $(if $(KERNEL_IN_UBI),--kernel $(IMAGE_KERNEL)) \
131 - $(foreach part,$(UBINIZE_PARTS),--part $(part)) \
132 - $(IMAGE_ROOTFS) \
133 - $@.tmp \
134 - -p $(BLOCKSIZE:%k=%KiB) -m $(PAGESIZE) \
135 - $(if $(SUBPAGESIZE),-s $(SUBPAGESIZE)) \
136 - $(if $(VID_HDR_OFFSET),-O $(VID_HDR_OFFSET)) \
137 - $(UBINIZE_OPTS)
138 - cat $@.tmp >> $@
139 - rm $@.tmp
140 -endef{{/code}}
141 -~{~{/code}}
20 +