Configurar la red

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This page is a translated version of the page Handbook:AMD64/Installation/Networking and the translation is 100% complete.
AMD64 Handbook
Installation
About the installation
Choosing the media
Configuring the network
Preparing the disks
The stage file
Installing base system
Configuring the kernel
Configuring the system
Installing tools
Configuring the bootloader
Finalizing
Working with Gentoo
Portage introduction
USE flags
Portage features
Initscript system
Environment variables
Working with Portage
Files and directories
Variables
Mixing software branches
Additional tools
Custom package repository
Advanced features
OpenRC network configuration
Getting started
Advanced configuration
Modular networking
Wireless
Adding functionality
Dynamic management


¿Es posible que simplemente funcione?

Si su sistema está conectado a una red Ethernet con un servidor DHCP, es muy probable que la configuración de red se haya detectado automáticamente. En ese caso, debería ser capaz de trabajar con las órdenes que hacen uso de la red y que están en el medio de instalación como son: ssh, scp, ping, irssi, wget, y links, entre otras.

Usar DHCP

DHCP (Protocolo de Configuración Dinámica del Sistema) hace posible recibir automáticamente su información de red (dirección IP, máscara de red, dirección de difusión, pasarela, servidores de nombres etc.). Esto solo funciona si dispone de un servidor DHCP en su red (o si su proveedor de servicios de internet (ISP) le ofrece el servicio DHCP). Para conseguir que su interfaz de red reciba esta información automáticamente use dhcpcd:

DHCP requires that a server be running on the same Layer 2 (Ethernet) segment as the client requesting a lease. DHCP is often used on RFC1918 (private) networks, but is also used to acquire public IP information from ISPs.

Consejo
Official Gentoo boot media runs dhcpcd automatically at startup. This behavior can be disabled by adding the nodhcp argument to the boot media kernel commandline.

If it is not already running, dhcpcd can be started on enp1s0 with:

root #dhcpcd eth0

Algunos administradores de red requieren que utilice el nombre de equipo y de dominio que proporciona el servidor DHCP. Si es el caso, utilice:

root #dhcpcd -HD eth0

To stop dhcpcd, -x can be used:

root #dhcpcd -x
sending signal Term to pid 10831
waiting for pid 10831 to exit
See also
Dhcpcd usage

Probar la red

A properly configured default route is a critical component of Internet connectivity, route configuration can be checked with:

root #ip route
default via 192.168.0.1 dev enp1s0

If no default route is defined, Internet connectivity is unavailable, and additional configuration is required.

Basic internet connectivity can be confirmed with a ping:

root #ping -c 3 1.1.1.1
Consejo
It's helpful to start by pinging a known IP address instead of a hostname. This can isolate DNS issues from basic Internet connectivity issues.

Outbound HTTPS access and DNS resolution can be confirmed with:

root #curl --location gentoo.org --output /dev/null

Si todo lo anterior funciona, puede saltarse el resto del capítulo e ir al siguiente paso de las instrucciones de instalación (Preparar los discos).

If curl reports an error, but Internet-bound pings work, DNS may need configuration.

If Internet connectivity has not been established, first interface information should be verified, then:

Determinar los nombres de las interfaces

If networking doesn't work out of the box, additional steps must be taken to enable Internet connectivity. Generally, the first step is to enumerate host network interfaces.

Como alternativa a ifconfig, se puede utilizar la orden ip para determinar los nombres de los adaptadores. El siguiente ejemplo muestra la salida de ip addr (de otro sistema, por tanto la información mostrada es diferente a la del ejemplo anterior):

The link argument can be used to display network interface links:

root #ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
4: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
    link/ether e8:40:f2:ac:25:7a brd ff:ff:ff:ff:ff:ff

The address argument can be used to query device address information:

root #ip addr
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether e8:40:f2:ac:25:7a brd ff:ff:ff:ff:ff:ff
    inet 10.0.20.77/22 brd 10.0.23.255 scope global eno1
       valid_lft forever preferred_lft forever
    inet6 fe80::ea40:f2ff:feac:257a/64 scope link 
       valid_lft forever preferred_lft forever

The output of this command contains information for each network interface on the system. Entries begin with the device index, followed by the device name: enp1s0.

Consejo
Si no se muestran adaptadores cuando se utiliza la orden estándar ifconfig, se puede intentar utilizar la misma orden con la opción -a. Esta opción fuerza a la utilidad a mostrar todos los adaptadores de red detectados por el sistema aunque se encuentren desactivados. Si no se obtienen resultados con ifconfig -a entonces falta el hardware o no se ha cargado el controlador del adaptador en el núcleo. Ambas situaciones no se tratar en este manual. Pedir ayuda en el canal #gentoo (webchat).

En el resto de este documento, el manual asume que el adaptador de red operativo se llama eth0.

Como consecuencia de la transición hacia los nombres predecibles de las interfaces de red, el nombre de la interfaz en su sistema puede diferir bastante del antiguo nombre convencional eth0. Los medios de instalación actuales pueden mostrar nombres regulares de interfaces de red como eno0, ens1 o enp5s0. Busque la interfaz en la salida de ifconfig que tenga una dirección IP relacionada con su red local.

Optional: Application specific configuration

The following methods are not generally required, but may be helpful in situations where additional configuration is required for Internet connectivity.

Opcional: Configure el Proxy

Si accede a Internet a través de un proxy, podría necesitar configurar la información del proxy durante la instalación. Es muy sencillo definir un proxy: tan solo necesita definir la variable que contiene la información del mismo.

Certain text-mode web browsers such as links can also make use of environment variables that define web proxy settings; in particular for the HTTPS access it also will require the https_proxy environment variable to be defined. While Portage will be influenced without passing extra run time parameters during invocation, links will require proxy settings to be set.

En la mayoría de los casos, puede definir las variables usando simplemente el nombre del servidor. Por ejemplo, asumimos que el proxy se llama proxy.gentoo.org y el puerto es el 8080.

Nota
The # symbol in the following commands is a comment. It has een added for clarity only and does not need to be typed when entering the commands.

Para usar un proxy HTTP (para tráfico HTTP y HTTPS):

root #export http_proxy="http://proxy.gentoo.org:8080"

Si su proxy requiere un nombre de usuario y una contraseña, debería usar la siguiente sintaxis para la variable:

CÓDIGO Añadir un usuario/contraseña a la variable del proxy
http://username:password@proxy.gentoo.org:8080

Start links using the following parameters for proxy support:

user $links -http-proxy ${http_proxy} -https-proxy ${https_proxy}

Para usar un proxy de FTP:

root #export ftp_proxy="ftp://proxy.gentoo.org:8080"

Start links using the following parameter for a FTP proxy:

user $links -ftp-proxy ${ftp_proxy}

Para usar un proxy para RSYNC:

root #export RSYNC_PROXY="proxy.gentoo.org:8080"

Alternativa: utilizar PPP

If PPPoE is required for Internet access, the Gentoo boot media includes the pppoe-setup script to simplify ppp configuration.

During setup, pppoe-setup will ask for:

  • The name of the Ethernet interface connected to the ADSL modem.
  • The PPPoE username and password.
  • DNS server IPs.
  • Whether or not a firewall is needed.
root #pppoe-setup
root #pppoe-start

In the event of failure, credentials in /etc/ppp/pap-secrets or /etc/ppp/chap-secrets should be verified. If credentials are correct, PPPoE Ethernet interface selection should be checked.

Alternativa: Usar PPTP

Si requiere soporte PPTP, puede usar pptpclient que se incluye en los CDs de instalación. Pero primero debe asegurarse de que su configuración es correcta. Edite /etc/ppp/pap-secrets o /etc/ppp/chap-secrets ya que contiene la combinación correcta de usuario/contraseña:

Edit /etc/ppp/pap-secrets or /etc/ppp/chap-secrets so it contains the correct username/password combination:

root #nano -w /etc/ppp/chap-secrets

Ajuste ahora /etc/ppp/options.pptp si es necesario:

root #nano -w /etc/ppp/options.pptp

Cuando todo esté listo, ejecute pptp (junto con las opciones que no se pudieron poner en options.pptp) para conectar al servidor:

root #pptp <server ipv4 address>

Preparar el acceso inalámbrico

Advertencia
Do not use WEP unless it is the only option. WEP provides essentially no security over an open network.
Nota
El soporte para la orden iw podría ser específico de algunas arquitecturas. Si la orden no está disponible mire si el paquete net-wireless/iw está disponible para la arquitectura en cuestión. La órden iw no estará disponible a menos que el paquete net-wireless/iw haya sido instalado.

Si está empleando una tarjeta inalámbrica (802.11), quizá necesite configurar sus opciones antes seguir. Para revisar la configuración inalámbrica actual de su tarjeta, puede utilizar iw. Al ejecutar iw se debería mostrar algo como esto:

root #iw dev wlp9s0 info
Interface wlp9s0
	ifindex 3
	wdev 0x1
	addr 00:00:00:00:00:00
	type managed
	wiphy 0
	channel 11 (2462 MHz), width: 20 MHz (no HT), center1: 2462 MHz
	txpower 30.00 dBm

Para comprobar la conexión actual:

root #iw dev wlp9s0 link
Not connected.

o

root #iw dev wlp9s0 link
Connected to 00:00:00:00:00:00 (on wlp9s0)
	SSID: GentooNode
	freq: 2462
	RX: 3279 bytes (25 packets)
	TX: 1049 bytes (7 packets)
	signal: -23 dBm
	tx bitrate: 1.0 MBit/s
Nota
Algunas tarjetas inalámbricas pueden tener un nombre de dispositivo como wlan0 o ra0 en lugar de wlp9s0. Lanzar ip link para determinar el nombre correcto del dispositivo.

Para la mayoría de los usuarios, solo hay dos ajustes necesarios para conectarse, el ESSID (también conocido como nombre de red inalámbrica) y, opcionalmente, la clave WEP.

  • En primer lugar, asegurarse de que la interfaz está activa:
root #ip link set dev wlp9s0 up
  • Para conectar a una red abierta llamada NodoGentoo:
root #iw dev wlp9s0 connect -w NodoGentoo
  • Para conectar con una clave WEP hexadecimal, anteponer la clave con d::
root #iw dev wlp9s0 connect -w GentooNode key 0:d:1234123412341234abcd
  • Para conectar con una clave WEP ASCII:
root #iw dev wlp9s0 connect -w GentooNode key 0:alguna-contraseña
Nota
Si la red inalámbrica está configurada para usar claves WPA o WPA2, tendrá que usar wpa_supplicant. Para más información acerca de la configuración de redes inalámbricas en Gentoo Linux, por favor lea el capítulo Redes Inalámbricas del Manual Gentoo.

Puede volver a comprobar la configuración inalámbrica utilizando iw dev wlp9s0 link. Una vez que tenga la conexión funcionando, puede continuar configurando las opciones de red de nivel IP como se describe en la siguiente sección (Entender la terminología de red) o utilizar la herramienta net-setup como hemos descrito anteriormente.

Configuración Automática de Red

In cases where automatic network configuration is unsuccessful, the Gentoo boot media provides scripts to aid in network configuration. net-setup can be used to configure wireless network information and static IPs.

root #net-setup eth0

net-setup le hará algunas preguntas sobre su entorno de red. Cuando lo haya completado, debería disponer de una conexión de red funcionando. Pruebe su conexión de red como se especificó anteriormente. Si los resultados son positivos, ¡felicidades! Sáltese el resto de esta sección y continúe con Preparar los discos.

Importante
Network status should be tested after any configuration steps are taken. In the event that configuration scripts do not work, manual network configuration is required.

Entender la terminología de red

If all of the above fails, the network must be configured manually. This is not particularly difficult, but should be done with consideration. This section serves to clarify terminology and introduce users to basic networking concepts pertaining to manually configuring an Internet connection.

Consejo
Some CPE (Carrier Provided Equipment) combines the functions of a router, access point, modem, DHCP server, and DNS server into one unit. It's important to differentiate the functions of a device from the physical appliance.

Interfaces and addresses

Network interfaces are logical representations of network devices. An interface needs an address to communicate with other devices on the network. While only a single address is required, multiple addresses can be assigned to a single interface. This is especially useful for dual stack (IPv4 + IPv6) configurations.

For consistency, this primer will assume the interface enp1s0 will be using the address 192.168.0.2.

Importante
IP addresses can be set arbitrarily. As a result, it's possible for multiple devices to use the same IP address, resulting in an address conflict. Address conflicts should be avoided by using DHCP or SLAAC.
Consejo
IPv6 typically uses StateLess Address AutoConfiguration (SLAAC) for address configuration. In most cases, manually setting IPv6 addresses is a bad practice. If a specific address suffix is preferred, interface identification tokens can be used.

Networks and CIDR

Once an address is chosen, how does a device know how to talk to other devices?

IP addresses are associated with networks. IP networks are contiguous logical ranges of addresses.

Classless Inter-Domain Routing or CIDR notation is used to distinguish network sizes.

  • The CIDR value, often notated starting with a /, represents the size of the network.
    • The formula 2 ^ (32 - CIDR) can be used to calculate network size.
    • Once network size is calculated, usable node count must be reduced by 2.
      • The first IP in a network is the Network address, and the last is typically the Broadcast address. These addresses are special and cannot be used by normal hosts.
Consejo
The most common CIDR values are /24, and /32, representing 254 nodes and a single node respectively.

A CIDR of /24 is the de-facto default network size. This corresponds to a subnet mask of 255.255.255.0, where the last 8 bits are reserved for IP addresses for nodes on a network.

The notation: 192.168.0.2/24 can be interpreted as:

  • The address 192.168.0.2
  • On the network 192.168.0.0
  • With a size of 254 (2 ^ (32 - 24) - 2)
    • Usable IPs are in the range 192.168.0.1 - 192.168.0.254
  • With a broadcast address of 192.168.0.255
    • In most cases, the last address on a network is used as the broadcast address, but this can be changed.

Using this configuration, a device should be able to communicate with any host on the same network (192.168.0.0).

The Internet

Once a device is on a network, how does it know how to talk to devices on the Internet?

To communicate with devices outside of local networks, routing must be used. A router is simply a network device that forwards traffic for other devices. The term default route or gateway typically refers to whatever device on the current network is used for external network access.

Consejo
It's a standard practice to make the gateway the first or last IP on a network.

If an Internet-connected router is available at 192.168.0.1, it can be used as the default route, granting Internet access.

To summarize:

  • Interfaces must be configured with an address and network information, such as the CIDR value.
  • Local network access is used to access a router on the same network.
  • The default route is configured, so traffic destined for external networks is forwarded to the gateway, providing Internet access.

The Domain Name System

Remembering IPs is hard. The Domain Name System was created to allow mapping between Domain Names and IP addresses.

Linux systems use /etc/resolv.conf to define nameservers to be used for DNS resolution.

Consejo
Many routers can also function as a DNS server, and using a local DNS server can augment privacy and speed up queries through caching.

Many ISPs run a DNS server that is generally advertised to the gateway over DHCP. Using a local DNS server tends to improve query latency, but most public DNS servers will return the same results, so server usage is largely based on preference.

Configuración Manual de la Red

Interface address configuration

Importante
When manually configuring IP addresses, the local network topology must be considered. IP addresses can be set arbitrarily; conflicts may cause network disruption.

To configure enp1s0 with the address 192.168.0.2 and CIDR /24:

root #ip address add 192.168.0.2/24 dev enp1s0
Consejo
The start of this command can be shortened to ip a.

Default route configuration

Configuring address and network information for an interface will configure link routes, allowing communication with that network segment:

root #ip route
192.168.0.0/24 dev enp1s0 proto kernel scope link src 192.168.0.2
Consejo
This command can be shortened to ip r.

The default route can be set to 192.168.0.1 with:

root #ip route add default via 192.168.0.1

DNS configuration

Nameserver info is typically acquired using DHCP, but can be set manually by adding nameserver entries to /etc/resolv.conf.

Advertencia
If dhcpcd is running, changes to /etc/resolv.conf will not persist. Status can be checked with ps x | grep dhcpcd.

nano is included in Gentoo boot media and can be used to edit /etc/resolv.conf with:

root #nano -w /etc/resolv.conf

Lines containing the keyword nameserver followed by a DNS server IP address are queried in order of definition:

ARCHIVO /etc/resolv.confUse Quad9 DNS.
nameserver 9.9.9.9
nameserver 149.112.112.112
ARCHIVO /etc/resolv.confUse Cloudflare DNS.
nameserver 1.1.1.1
nameserver 1.0.0.1

DNS status can be checked by pinging a domain name:

root #ping -c 3 gentoo.org

Once connectivity has been verified, continue with Preparing the disks.