AFTERBOOT(8)

AFTERBOOT(8) | System Manager's Manual | AFTERBOOT(8)

# NAME

`afterboot` — things to check after the first complete boot

# DESCRIPTION

## Starting Out

This document attempts to list items for the system administrator to check and set up after the installation and first complete boot of the system. The idea is to create a list of items that can be checked off so that you have a warm fuzzy feeling that something obvious has not been missed. A basic knowledge of UNIX is assumed.

Complete instructions for correcting and fixing items is not provided. There are manual pages and other methodologies available for doing that. For example, to view the man page for the ls(1) command, type:

    man 1 ls

Administrators will rapidly become more familiar with NetBSD if they get used to using the manual pages.

## Login

On a fresh install with no other user accounts, login as “`root`”. You can do so on the console, or over the network using ssh(1). If you have enabled the SSH daemon (see sshd(8)) and wish to allow root logins over the network, edit the /etc/ssh/sshd_config file and set “PermitRootLogin” to “yes” (see sshd_config(5)). The default is to not permit root logins over the network after fresh install in NetBSD.

Upon successful login on the console, you may see the message “We recommend creating a non-root account...”. For security reasons, it is bad practice to login as root during regular use and maintenance of the system. In fact, the system will only let you login as root on a secure terminal. By default, only the console is considered to be a secure terminal. Instead, administrators are encouraged to add a “regular” user, add said user to the “wheel” group, then use the su(1) command when root privileges are required:

    useradd -G wheel -m myuser
    passwd myuser

## Root password

Change the password for the root user. (Note that throughout the documentation, the term “superuser” is a synonym for the root user.) Choose a password that has numbers, digits, and special characters (not space) as well as from the upper and lower case alphabet. Do not choose any word in any language. It is common for an intruder to use dictionary attacks. Type the command `/usr/bin/passwd` to change it.

It is a good idea to always specify the full path name for both the passwd(1) and su(1) commands as this inhibits the possibility of files placed in your execution `PATH` for most shells. Furthermore, the superuser's `PATH` should never contain the current directory (“.”).

## System date

Check the system date with the date(1) command. If needed, change the date, and/or change the symbolic link of /etc/localtime to the correct time zone in the /usr/share/zoneinfo directory.

Examples:

`date 202010051820`
  Set the current date to October 5th, 2020 6:20pm.
`ln -fs /usr/share/zoneinfo/Europe/Helsinki /etc/localtime`
  Set the time zone to Eastern Europe Summer Time.

## Console settings

One of the first things you will likely need to do is to set up your keyboard map (and maybe some other aspects about the system console). To change your keyboard layout, edit the “encoding” variable found in /etc/wscons.conf.

wscons.conf(5) contains more information about this file.

## Security alerts

All significant and easily fixed problems will be reported at the security advisories web page. It is recommended that you check this page regularly.

Additionally, you should set “fetch_pkg_vulnerabilities=YES” in /etc/daily.conf to allow your system to automatically update the local database of known vulnerable packages to the latest version available on-line. The system will later check, on a daily basis, if any of your installed packages are vulnerable based on the contents of this database. See daily.conf(5) and security.conf(5) for more details.

## Entropy

If your machine does not have a hardware random number generator, it may not be safe to use on the internet until it has enough entropy to generate unpredictable secrets for programs like web browsers and ssh(1). You can use rndctl(8) to list the entropy sources with `rndctl -l`, or save entropy from another machine running NetBSD with `rndctl -S` and load it on this one with `rndctl -L` (as long as there are no eavesdroppers on the medium between the two machines). See entropy(7) for more details.

## Check hostname

Use the `hostname` command to verify that the name of your machine is correct. See the man page for hostname(1) if it needs to be changed. You will also need to change the contents of the “hostname” variable in /etc/rc.conf or edit the /etc/myname file to have it stick around for the next reboot. Note that “hostname” is supposed include a domainname, and that this should not be confused with YP (NIS) domainname(1). If you are using dhcpcd(8) to configure network interfaces, it might override these local hostname settings if your DHCP server specifies client's hostname with other network configurations.

## Verify network interface configuration

The first thing to do is an `ifconfig -a` to see if the network interfaces are properly configured. Correct by editing /etc/ifconfig.interface or the corresponding “ifconfig_interface” variable in rc.conf(5) (where interface is the interface name, e.g., “le0”) and then using ifconfig(8) to manually configure it if you do not wish to reboot.

Alternatively, many networks allow interfaces to be configured automatically via DHCP. To get dhcpcd(8) to start automatically on boot, you will need to have this line in /etc/rc.conf:

`dhcpcd=YES`

See dhcpcd(8) and dhcpcd.conf(5) for more information on setting up a DHCP client. For information on setting up Wi-Fi, see Wireless networking.

You can add new “virtual interfaces” by adding the required entries to /etc/ifconfig.interface. Read the ifconfig.if(5) man page for more information on the format of /etc/ifconfig.interface files. The loopback interface will look something like:

    lo0: flags=8009<UP,LOOPBACK,MULTICAST> mtu 32972
    	inet 127.0.0.1 netmask 0xff000000
    	inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
    	inet6 ::1 prefixlen 128

an Ethernet interface something like:

    le0: flags=9863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST>
    	inet 192.168.4.52 netmask 0xffffff00 broadcast 192.168.4.255
    	inet6 fe80::5ef0:f0f0%le0 prefixlen 64 scopeid 0x1

and a PPP interface something like:

    ppp0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST>
            inet 203.3.131.108 --> 198.181.0.253 netmask 0xffff0000

See mrouted(8) for instructions on configuring multicast routing.

## Check routing tables

Issue a `netstat -rn` command. The output will look something like:

    Routing tables

    Internet:
    Destination    Gateway           Flags  Refs     Use  Mtu  Interface
    default        192.168.4.254     UGS      0 11098028    -  le0
    127            127.0.0.1         UGRS     0        0    -  lo0
    127.0.0.1      127.0.0.1         UH       3       24    -  lo0
    192.168.4      link#1            UC       0        0    -  le0
    192.168.4.52   8:0:20:73:b8:4a   UHL      1     6707    -  le0
    192.168.4.254  0:60:3e:99:67:ea  UHL      1        0    -  le0

    Internet6:
    Destination        Gateway       Flags  Refs  Use     Mtu  Interface
    ::/96              ::1           UGRS     0     0   32972  lo0 =>
    ::1                ::1           UH       4     0   32972  lo0
    ::ffff:0.0.0.0/96  ::1           UGRS     0     0   32972  lo0
    fc80::/10          ::1           UGRS     0     0   32972  lo0
    fe80::/10          ::1           UGRS     0     0   32972  lo0
    fe80::%le0/64      link#1        UC       0     0    1500  le0
    fe80::%lo0/64      fe80::1%lo0   U        0     0   32972  lo0
    ff01::/32          ::1           U        0     0   32972  lo0
    ff02::%le0/32      link#1        UC       0     0    1500  le0
    ff02::%lo0/32      fe80::1%lo0   UC       0     0   32972  lo0

The default gateway address is stored in the “defaultroute” variable in /etc/rc.conf, or in the file /etc/mygate. If you need to edit this file, a painless way to reconfigure the network afterwards is to issue

    service network restart

Or, you may prefer to manually configure using a series of `route add` and `route delete` commands (see route(8)). If you run dhcpcd(8) you will have to kill it by running

    service dhcpcd stop

before you flush the routes.

If you wish to route packets between interfaces, add one or both of the following directives (depending on whether IPv4 or IPv6 routing is required) to /etc/sysctl.conf:

`net.inet.ip.forwarding=1`
`net.inet6.ip6.forwarding=1`

As an alternative, compile a new kernel with the “GATEWAY” option. Packets are not forwarded by default, due to RFC requirements.

## Device nodes

By default, nodes are created in /dev for a fairly typical number of devices.

However, if this system has a large number of devices connected (e.g. for large scale storage), you may want to enable devpubd(8) to ensure a sufficient number of nodes are available. Set “devpubd=YES” in /etc/rc.conf to create nodes automatically during system runtime. You can also run the node creation script by hand:

    cd /dev && sh MAKEDEV

## Secure Shell (SSH)

By default, all services are disabled in a fresh NetBSD installation, and SSH is no exception. You may wish to enable it so you can remotely control your system. Set “sshd=YES” in /etc/rc.conf and then starting the server with the command

    service sshd start

The first time the server is started, it will generate a new keypair, which will be stored inside the directory /etc/ssh.

## Host names and DNS

The system resolves host names according the rules for hosts in the name service switch configuration at /etc/nsswitch.conf. By default, it will query /etc/hosts first, and then the DNS resolver specified in /etc/resolv.conf.

Multicast DNS and DNS Service Discovery are usually not enabled by default on a fresh NetBSD system, and can be enabled by setting “mdnsd=YES” in /etc/rc.conf, and either rebooting or running the following command:

    service mdnsd start

You may also wish to enable mdnsd as a source for host lookups in /etc/nsswitch.conf, see nsswitch.conf(5).

If your network does not have a usable DNS resolver, e.g. one provided by DHCP, you can run a local caching recursive resolver by setting “named=YES” in /etc/rc.conf and either rebooting or running the following command:

    service named start

named(8) is configured in /etc/named.conf by default to run as a local caching recursive resolver. Then, to make the system use it, put the following in /etc/resolv.conf:

    nameserver 127.0.0.1

## Wireless networking

To configure the system to connect to a Wi-Fi network with a password using WPA:

    wpa_passphrase networkname password >> /etc/wpa_supplicant.conf

To configure the system to connect to an open wireless network with no password, edit /etc/wpa_supplicant.conf instead of using wpa_passphrase(8):

    network={
    	ssid="Public-WiFi"
    	key_mgmt=NONE
    	priority=100
    }

Then bring up the interface and start the necessary daemons:

    ifconfig iwm0 up
    service wpa_supplicant onestart
    service dhcpcd onestart

To automatically connect at boot, add the following to /etc/rc.conf:

`ifconfig_iwm0="up"`
`dhcpcd=YES`
`wpa_supplicant=YES`

While using wpa_supplicant(8), you can easily retrieve network scan results with wpa_cli(8):

    wpa_cli scan_results

Or trigger a rescan:

    wpa_cli scan

## RPC-based network services

Several services depend on the RPC portmapper rpcbind(8) - formerly known as `portmap` - being running for proper operation. This includes YP (NIS) and NFS exports, among other services. To get the RPC portmapper to start automatically on boot, you will need to have this line in /etc/rc.conf:

`rpcbind=YES`

## YP (Network Information Service) Setup

Check the YP domain name with the domainname(1) command. If necessary, correct it by editing the /etc/defaultdomain file or by setting the “domainname” variable in /etc/rc.conf. The /etc/rc.d/network script reads this file on bootup to determine and set the domain name. You may also set the running system's domain name with the domainname(1) command. To start YP client services, simply run `ypbind`, then perform the remaining YP activation as described in passwd(5) and group(5).

In particular, to enable YP passwd support, you'll need to update /etc/nsswitch.conf to include “nis” for the “passwd” and “group” entries. A traditional way to accomplish the same thing is to add following entry to local passwd database via vipw(8):

    +:*::::::::

Note this entry has to be the very last one. This traditional way works with the default nsswitch.conf(5) setting of “passwd”, which is “compat”.

There are many more YP man pages available to help you. You can find more information by starting with nis(8).

## Check disk mounts

Check that the disks are mounted correctly by comparing the /etc/fstab file against the output of the mount(8) and df(1) commands. Example:

    # cat /etc/fstab
    /dev/sd0a / ffs     rw              1 1
    /dev/sd0b none swap sw
    /dev/sd0e /usr ffs  rw              1 2
    /dev/sd0f /var ffs  rw              1 3
    /dev/sd0g /tmp ffs  rw              1 4
    /dev/sd0h /home ffs rw              1 5

    # mount
    /dev/sd0a on / type ffs (local)
    /dev/sd0e on /usr type ffs (local)
    /dev/sd0f on /var type ffs (local)
    /dev/sd0g on /tmp type ffs (local)
    /dev/sd0h on /home type ffs (local)

    # df
    Filesystem  1024-blocks     Used    Avail Capacity  Mounted on
    /dev/sd0a         22311    14589     6606    69%    /
    /dev/sd0e        203399   150221    43008    78%    /usr
    /dev/sd0f         10447      682     9242     7%    /var
    /dev/sd0g         18823        2    17879     0%    /tmp
    /dev/sd0h          7519     5255     1888    74%    /home

    # pstat -s
    Device      512-blocks     Used    Avail Capacity  Priority
    /dev/sd0b       131072    84656    46416    65%    0

Edit /etc/fstab and use the mount(8) and umount(8) commands as appropriate. Refer to the above example and fstab(5) for information on the format of this file.

You may wish to do NFS mounts now too, or you can do them later.

## Clock synchronization

In order to make sure the system clock is synchronized to that of a publicly accessible NTP server, make sure that /etc/rc.conf contains the following:

`ntpdate=YES`
`ntpd=YES`

See date(1), ntpdate(8), ntpd(8), rdate(8), and timed(8) for more information on setting the system's date.

## Installing packages

The NetBSD packages collection, pkgsrc, includes a large set of third-party software. A lot of it is available as binary packages that you can download from https://cdn.NetBSD.org/pub/pkgsrc/packages/NetBSD/ or a mirror.

For most users, using pkgin to manage binary packages is recommended.

To install pkgin, if it was not done by the installer:

    PKG_PATH=https://cdn.NetBSD.org/pub/pkgsrc/packages/NetBSD/[...]
    export PKG_PATH
    pkg_add pkgin
    pkgin update
    pkgin install bash mpg123 fluxbox ...

See https://www.pkgsrc.org/ and pkgsrc/doc/pkgsrc.txt for more details.

# CHANGING /etc FILES

The system should be usable now, but you may wish to do more customizing, such as adding users, etc. Many of the following sections may be skipped if you are not using that package (for example, skip the Kerberos section if you won't be using Kerberos). We suggest that you `cd /etc` and edit most of the files in that directory.

Note that the /etc/motd file is modified by /etc/rc.d/motd whenever the system is booted. To keep any custom message intact, ensure that you leave two blank lines at the top, or your message will be overwritten.

## Add new users

To add new users and groups, there are useradd(8) and groupadd(8); see also user(8) for further programs for user and group manipulation. You may use vipw(8) to add users to the /etc/passwd file and edit /etc/group by hand to add new groups. The manual page for su(1), tells you to make sure to put people in the ‘wheel’ group if they need root access (non-Kerberos). For example:

    wheel:*:0:root,myself

Follow instructions for kerberos(8) if using Kerberos for authentication.

## System boot scripts and /etc/rc.local

/etc/rc and the /etc/rc.d/* scripts are invoked at boot time after single user mode has exited, and at shutdown. The whole process is controlled by the master script /etc/rc. This script should not be changed by administrators.

The directory /etc/rc.d contains a series of scripts used at startup/shutdown, called by /etc/rc. /etc/rc is in turn influenced by the configuration variables present in /etc/rc.conf.

The script /etc/rc.local is run as the last thing during multiuser boot, and is provided to allow any other local hooks necessary for the system.

## rc.conf

To enable or disable various services on system startup, corresponding entries can be made in /etc/rc.conf. You can take a look at /etc/defaults/rc.conf to see a list of default system variables, which you can override in /etc/rc.conf. Note you are not supposed to change /etc/defaults/rc.conf directly, edit only /etc/rc.conf. See rc.conf(5) for further information.

## Automounter daemon (AMD)

To use the amd(8) automounter, create the /etc/amd directory, copy example config files from /usr/share/examples/amd to /etc/amd and customize them as needed. Alternatively, you can get your maps with YP.

## Concatenated disks (ccd)

If you are using ccd(4) concatenated disks, edit /etc/ccd.conf. You may wish to take a look to ccdconfig(8) for more information about this file. Use the `ccdconfig -U` command to unload and the `ccdconfig -C` command to create tables internal to the kernel for the concatenated disks. You then mount(8), umount(8), and edit /etc/fstab as needed.

## NetBSD Packet Filter

npf(7) is the default firewall used on NetBSD. You may wish to enable it if your machine is connected directly to the internet. To do this, edit /etc/npf.conf and set “npf=YES” in /etc/rc.conf. Configuration examples for NPF can be found in /usr/share/examples/npf. Before installing a configuration, you can validate it with npfctl(8).

## X Display Manager

If you've installed X, you may want to turn on xdm(1), the X Display Manager. To do this, set “xdm=YES” in /etc/rc.conf.

## Printers

Edit /etc/printcap and /etc/hosts.lpd to get any printers set up. Consult lpd(8) and printcap(5) if needed.

## Internet Services (inetd)

Various internet services can be enabled in /etc/inetd.conf, including httpd(8) and finger(1). Note that by default all services are disabled for security reasons. Only add things that are really needed.

## Kerberos

If you are going to use Kerberos for authentication, see kerberos(8) and “info heimdal” for more information. If you already have a Kerberos master, change directory to /etc/kerberosV and configure. Remember to get a srvtab from the master so that the remote commands work.

## Mail Aliases

Check /etc/mail/aliases and update appropriately if you want e-mail to be routed to non-local addresses or to different users.

Run newaliases(1) after changes.

## Postfix

NetBSD uses Postfix as its Mail Transfer Agent. Postfix is started by default, but its initial configuration does not cause it to listen on the network for incoming connections. To configure Postfix, see /etc/postfix/main.cf and /etc/postfix/master.cf. If you wish to use a different MTA (e.g., sendmail), install your MTA of choice and edit /etc/mailer.conf to point to the proper binaries.

## DHCP server

If this is a DHCP server, edit /etc/dhcpd.conf and /etc/dhcpd.interfaces as needed. You will have to make sure /etc/rc.conf has “dhcpd=YES” or run dhcpd(8) manually.

## Bootparam server

If this is a Bootparam server, edit /etc/bootparams as needed. You will have to turn it on in /etc/rc.conf by adding “bootparamd=YES”.

## NFS server

If this is an NFS server, make sure /etc/rc.conf has:

    nfs_server=YES
    mountd=YES
    rpcbind=YES

Edit /etc/exports and get it correct. After this, you can start the server by issuing:

    service rpcbind start
    service mountd start
    service nfsd start

which will also start dependencies.

## HP remote boot server

Edit /etc/rbootd.conf if needed for remote booting. If you do not have HP computers doing remote booting, do not enable this.

## Daily, weekly, monthly scripts

Look at and possibly edit the /etc/daily.conf, /etc/weekly.conf, and /etc/monthly.conf configuration files. You can check which values you can set by looking to their matching files in /etc/defaults. Your site specific things should go into /etc/daily.local, /etc/weekly.local, and /etc/monthly.local.

These scripts have been limited so as to keep the system running without filling up disk space from normal running processes and database updates. (You probably do not need to understand them.)

## Other files in /etc

Look at the other files in /etc and edit them as needed. (Do not edit files ending in .db — like pwd.db, spwd.db, nor localtime, nor rmt, nor any directories.)

## Crontab (background running processes)

Check what is running by typing `crontab -l` as root and see if anything unexpected is present. Do you need anything else? Do you wish to change things? For example, if you do not like root getting standard output of the daily scripts, and want only the security scripts that are mailed internally, you can type `crontab -e` and change some of the lines to read:

    30  1  *  *  *   /bin/sh /etc/daily 2>&1 > /var/log/daily.out
    30  3  *  *  6   /bin/sh /etc/weekly 2>&1 > /var/log/weekly.out
    30  5  1  *  *   /bin/sh /etc/monthly 2>&1 > /var/log/monthly.out

See crontab(5).

## Next day cleanup

After the first night's security run, change ownerships and permissions on files, directories, and devices; root should have received mail with subject: "<hostname> daily insecurity output.". This mail contains a set of security recommendations, presented as a list looking like this:

    var/mail:
            permissions (0755, 0775)
    etc/daily:
            user (0, 3)

The best bet is to follow the advice in that list. The recommended setting is the first item in parentheses, while the current setting is the second one. This list is generated by mtree(8) using /etc/mtree/special. Use chmod(1), chgrp(1), and chown(8) as needed.

# SYSTEM TESTING

At this point, the system should be fully configured to your liking. It is now a good time to ensure that the system behaves according to its specifications and that it is stable on your hardware. Please refer to tests(7) for details on how to do so.

You can use ps(1), netstat(1), and fstat(1) to check on running processes, network connections, and opened files, respectively. Other tools you may find useful are systat(1) and top(1).

# SEE ALSO

chgrp(1), chmod(1), config(1), crontab(1), date(1), df(1), domainname(1), fstat(1), hostname(1), make(1), man(1), netstat(1), newaliases(1), passwd(1), pkg_add(1), ps(1), ssh(1), su(1), systat(1), top(1), xdm(1), ccd(4), aliases(5), crontab(5), dhcpcd.conf(5), exports(5), fstab(5), group(5), hosts(5), ifconfig.if(5), mailer.conf(5), named.conf(5), nsswitch.conf(5), passwd(5), printcap(5), rc.conf(5), resolv.conf(5), sshd_config(5), wpa_supplicant.conf(5), wscons.conf(5), hier(7), hostname(7), pkgsrc(7), tests(7), amd(8), ccdconfig(8), chown(8), devpubd(8), dhcpcd(8), dhcpd(8), dmesg(8), groupadd(8), ifconfig(8), inetd(8), kerberos(8), lpd(8), mdnsd(8), mount(8), mrouted(8), mtree(8), named(8), nis(8), ntpd(8), ntpdate(8), rbootd(8), rc(8), rdate(8), rmt(8), route(8), rpc.bootparamd(8), rpcbind(8), sshd(8), timed(8), umount(8), useradd(8), vipw(8), wpa_cli(8), wpa_supplicant(8), yp(8), ypbind(8)

# HISTORY

This document first appeared in OpenBSD 2.2. It has been adapted to NetBSD and first appeared in NetBSD 2.0.

June 4, 2021 | NetBSD 11.0