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diff --git a/README.networking b/README.networking deleted file mode 100644 index 835db50..0000000 --- a/README.networking +++ /dev/null @@ -1,554 +0,0 @@ -Slackware Network Configuration -=============================== - -Networking in Slackware is configured by the /etc/rc.d/rc.inet1 script, and the -configuration file /etc/rc.d/rc.inet1.conf. Wireless interfaces are configured -just like any network interface, but accept many more configuration parameters. - -The rc.inet1.conf file contains a series of variable array definitions, with -each array index corresponding to a single network interface. This means that -each set of parameters with an index of 0 configure the first interface (since -indexing starts at 0), parameters with an index of 1 configure the second -interface, and so on. Not all parameters need to be set for each type of -interface, or interface number. This is better illustrated with examples, -which you will find in the documentation below. - - -Starting and Stopping Interfaces --------------------------------- -The way to start networking (configuring all NICs, bringing the interfaces up, -and creating a default route, if required) is by running the command: - /etc/rc.d/rc.inet1 start -This command will configure all networking interfaces which are defined in the -configuration file, and is used at boot time to bring networking up. - -The counterpart to this is the: - /etc/rc.d/rc.inet1 stop -command, which will bring all networking to a stop. It is advised to use this -with caution as it can make your host completely inaccessable from the network. - -Restarting the whole network (all available network interfaces) and resetting -the default gateway (if set) is done in a similar fashion to starting it: - /etc/rc.d/rc.inet1 restart -And will first deconfigure all interfaces, before bringing them back up - which -is functionally equalivant to a 'stop' and 'start' operation. - -More specifically speaking, you can start/stop/restart any network interface on -an individual basis using the commands: - /etc/rc.d/rc.inet1 <interface>_start - /etc/rc.d/rc.inet1 <interface>_stop - /etc/rc.d/rc.inet1 <interface>_restart -where <interface> is the name of an existing network interface (eth0, eth1, -wlan0, etc). - - -Guided Networking Configuration -------------------------------- -The 'netconfig' script is capable of configuring basic networking parameters for -the first ethernet interface of the system, and writing an annotated -/etc/rc.d/rc.inet1.conf configuration file. 'netconfig' is usually invoked -during installation to configure the first ethernet interface of your freshly -installed system. - -'netconfig' is capable of configuring a set of IPv4 and/or IPv6 addresses for an -interface, or setting the interface to be configured using DHCP (both DHCPv4 and -DHCPv6) and IPv6 StateLess Address Auto Configuration (SLAAC). The default -gateways and nameservers can also be configured through the guided interface. - -The option to use NetworkManager for interface configuration (instead of -rc.inet1.conf) is also available. - -For most users with a single ethernet interface, and simple IP configuration -requirements, 'netconfig' can completely configure the networking sub-system for -you. - - -Deprecated and New IPv4 Configuration Syntax --------------------------------------------- -With the release of Slackware 15.0, several parameters used in older -rc.inet1.conf configurations have become deprecated and are substituted by a -new, singular, IP parameter for v4 addresses. - -Specifically, the following parameters used in previous rc.inet1.conf -configurations to configure IPv4 addresses have become deprecated: - IPADDR[x]="" - NETMASK[x]="" - IPALIASES[x]="" -These parameters should no longer be used in new configurations. - -New configurations should use the updated syntax parameter: - IPADDRS[x]="" -which can hold multiple, space delimited, IPv4 addresses with their CIDR -masks in order to configure an interface. - -The format for the addresses specified in this new parameter is: - IP-address/mask -For example: - IPADDRS[0]="192.168.0.1/24 10.10.10.10/8" -which would be the equilivant of old syntax: - IPADDR[0]="192.168.0.1" - NETMASK[0]="255.255.255.0" - IPALIASES[0]="10.10.10.10/8" - -If a mask (in CIDR notation) is not provided with the IP address in IPADDRS, it -is assumed to be /24 (aka, 255.255.255.0). A warning will also be emitted about -the missing mask. - -rc.inet1 is fully backwards compatible with the older syntax - old configuration -files will contiinue to be accepted for the foreseeable future, but 'netconfig' -has been adjusted to output the new syntax. - -Notes: - * When DHCP or SLAAC is used to dynamically configure the interface, IP - addresses specified in IPADDRS will be added to the interface as alias IPs. - However, any address specified in IPADDR is *not* added to the interface in - order to maintain backwards semantics with the pre 15.0 rc.inet1. - * Should an rc.inet1.conf contain both the IPADDR and IPADDRS parameters - (without DHCP or SLAAC being in use) the addresses listed in IPADDRS will be - added to the interface after the IPADDR address is set. - - -Manual Networking Configuration -------------------------------- -FIXME - - -IPv6 ----- - Overview - ~~~~~~~~ - - With the new IPv4 syntax detailed above, there is the addition of optional - configuration semantics for IPv6. - - The IPv6 capabilities in Slackware 15.0+ are as follows: - * Dual stack. Interfaces can be configured with an IPv4 address or an IPv6 - address, or both. - * Each interface can have single or multiple v4 and/or v6 IPs. - * Optional StateLess Address Auto Configuration (SLAAC) of v6 IP addresses, - for quick and easy IPv6 configuration on supported networks. - * DHCPv6 support for server controlled dynamic address configuration. - * Fixed IPv6 addresses configured interfaces. - - 'netconfig' can be used for guided configuration of all of the above features, - or they can be configured manually using the options below. - - - IPv6 Parameters - ~~~~~~~~~~~~~~~ - v6 IPs can be configured via SLAAC, DHCP6 or statically using the following - new options for rc.inet1.conf: - USE_SLAAC[x]="" Allow StateLess Address Auto Configuration of a - (potentially) globally routable v6 IP. With this - parameter set to "yes", the interface's v6 IP will ONLY - be configured via SLAAC, even if Router Advertisment - indicates DHCPv6 is available on the network - if SLAAC - is not available on the network, no IPv6 address will be - assigned. - - Since 'dhcpcd' is capable of handling SLAAC as well as - DHCPv6, it is better practice to set USE_DHCP6[x]="yes" - to perform full auto configuration instead. - - USE_DHCP6[x]="" Use 'dhcpcd' to configure the interface. This will - bring up the interface using DHCPv6, falling back to - SLAAC (if supported on the network), or will leave the - interface unconfigured after a timeout. When this - parameter is set to "yes", the USE_SLAAC[x] option is - ignored. - - This is the preferred option to configure an interface - dynamically - whether the network is setup for DHCPv6 or - SLAAC, 'dhcpcd' will be able to configure the interface. - - IP6ADDRS[x]="" The static v6 IP addresses for the interface. This - parameter takes a list of v6 IP addresses and prefix - lengths in CIDR notation, in a space delimited list. - For example: IP6ADDRS[x]="a:b:c:d:e::1/48 1:2:3:4::5/64" - - If a prefix length is not given (separated from the IP - address with a /), a length of 64 will be assumed, and - a warning emitted about the unset value. - - When either the USE_DHCP6[x] or USE_SLAAC[x] options are - set to "yes", the IP addresses listed in this parameter - are also added to the interface, but only upon sucessful - assigning of the dynamic IP address. - - A static gateway can be configured using this parameter: - GATEWAY6="" The default IPv6 gateway for the network. This is a - single IPv6 address in standard format, without a - prefix suffix. - - The following lesser used misc options can be used for tailouring of the IPv6 - configuration process: - USE_RA[x]="" Normally, unless USE_SLAAC[x]="yes" is set, Router - Advertisment (RA) is disabled for the interface as it - can result in extraneous routes being added to the - routing table. With this option set to "yes", RA - packets will be accepted on the interface even when DHCP - or fixed IP addressing is used, and the routes - advertised by the router will be added to the table. - - Conversely, if this parameter is explicitly set to "no", - RA will be disabled at all times - meaning SLAAC cannot - be performed even when USE_SLAAC[x]="yes" is set. The - default (unset) is to enable RA when SLAAC is in use, - and to disable it otherwise. - - The use of this parameter should rarely be required as - rc.inet1 will do the right thing. - - SLAAC_TIMEOUT[x]="" The time to wait (in seconds) for an interface to be - configured by SLAAC. When unset, the default is 15. - Some networks may require a longer period for the router - to broadcast an advertisement packet on the network, so - may need to increase this value. - - - Disabling IPv6 - ~~~~~~~~~~~~~~ - For some use cases, where IPv6 support is not required at all, disabling IPv6 - may be a better option than leaving the interface unconfigured. - - There are two similar methods which can be used to disable IPv6. Both of the - options involve creating (or replacing the content if it already exists in) - the file: - /etc/modprobe.d/ipv6.conf - (which overrides any configuration in the /lib/modprobe.d/ipv6.conf file), - with the content: - alias ipv6 off - alias net-pf-10 off - Or: - install ipv6 /bin/true - install net-pf-10 /bin/true - - It is important to disable both the 'ipv6' and 'net-pf-10' modules since the - module can be automatically loaded by either name. - - - Changes From Previous Behaviour - ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - * Previous to Slackware 15.0, if the network the host is connecting to is set - up for StateLess Address Auto Configuration (SLAAC), the host would bring up - an interface with a (potentially) globally routable IPv6 address with no - configuration by the user. This has been changed so that all network - configuration must be explicitly enabled. Thus, interfaces will no longer - automatically come up with a valid IPv6 address on networks which support - auto configuration, without enabling the USE_SLAAC[x]="yes" parameter for - the interface. This is a security enhancement. - - * Unless RA is explicitly enabled using the USE_RA[x]="yes" option, rc.inet1 - now disables RA (via the accept_ra tunable in /proc) for an interface before - trying to add any IPs configured for it. This prevents RA on the network - from automatically adding any routes to the table. When USE_SLAAC[x]="yes" - is set, RA is implicitly re-enabled for the interface (since SLAAC and RA - are usually used together on a network), unless explicitly disabled with - USE_RA[x]="no". This is a change from previous versions of Slackware, which - would auto configure routes without any user intevention. This is a - security enhancement. - - - Caveats - ~~~~~~~ - * When being configured with the USE_DHCP[x]="yes" and USE_DHCP6[x]="yes" - parameters for an interface (that is, configured to obtain both a v4 and v6 - addresses via DHCP), 'dhcpcd' will only wait until one type of IP is - obtained before backgrounding - it will not wait for both a v4 AND v6 to be - configured. This means there is no way to know if the interface has been - completely configured for both types of IP, as one type will continue to be - sought in the background; but MAY ultimately fail. This is an issue with - the way dhcpcd operates, not an issue with rc.inet1. - - -Bonding / Link Aggregation --------------------------- - Overview - ~~~~~~~~ - Bonding (or Link Aggregation) is a teccnique for combining two or more - physical interfaces into a single, logical, interface; a logical interface - which has all the capabilities of a single physical interface. - - The Slackware bonding options provide full support for the features offered by - the bonding kernel module, in the familiar Slackware parameter configuration - syntax. Included is the ability to select the bonding mode, easy addition of - interfaces to a bond using a new parameter in rc.inet1.conf, and the setting - of bonding module options via a new, generic, IFOPTS[x] parameter. - - At this time 'netconfig' is unable to configure bonded interfaces, so they - must be configured manually with the parameters detailed below. - - - Bonding Parameters - ~~~~~~~~~~~~~~~~~~ - Bonded interfaces can be configured via two new bond specific parameters for - use in rc.inet1.conf, plus the new, generic, IFOPTS[x] parameter. The new - bonding parameters are: - BONDNICS[x]="" The space delimited list of interfaces to add to this - bond. The interfaces will be brought up and configured - while bringing up the interface, so do not need to be - previously defined in rc.inet1.conf. A bond can be - created with only 1 interface, but does not become - useful until at least 2 interfaces are configured. - - BONDMODE[x]="" This parameter sets the bonding mode for the logical - interface. If not specified when BONDNICS[x] has been - used, the default is 'balance-rr'. See below for a - list of all bonding modes available. - - - Bonding Modes - ~~~~~~~~~~~~~ - When a bonded logical interface is created, it needs to operate in a - particular mode. By default that mode is 'balance-rr'. The following modes, - along with details of their functionallity, are available using the kernel - bonding driver: - 802.3ad Also known as LACP. This mode requires a switch that - supports an IEEE 802.3ad. The physical interfaces must - share the same speed and duplex settings and form a - logical interface which provides fault tolerance and - load balancing. - active-backup When in this mode only one interface set to active, - while all other interfaces are in the backup state. If - the active interface fails, a backup interface replaces - it as the only active interface in the bond. This mode - only provides fault tolerance, no load balancing. - This mode requires that the 'primary <interface>' - option be configured with the IFOPTS[x]="" parameter. - balance-alb The receiving packets are load balanced through Address - Resolution Protocol (ARP) negotiation. This mode - provides fault tolerance and load balancing. - balance-rr This mode is also known as round-robin mode. Packets - are sequentially transmitted and received through each - interface one by one. This mode provides load - balancing functionality along with fault tolerance. - This is the default mode of operation. - balance-tlb This mode ensures that outgoing traffic is distributed - according to the load on each physical interface. If - one interface fails to receive traffic, another - interface is assigned to the receiving role. This mode - provides fault tolerance and load balancing. - balance-xor The source MAC address uses eXclusive OR (XOR) logic - with the destination MAC address in order to determine - which physical interface the packet should be sent via. - This calculation ensures that the same physical (slave) - interface is selected for each destination host. If the - physical interface to be used is in a failed state, one - of the backup interfaces is used instead. This mode - provides fault tolerance and load balancing. - broadcast All packets are sent to all the physical (slaved) - interfaces at once. This mode provides fault tolerence - but may result in duplicate packets arriving at the - destination host, assuming they are not screened out by - networking hardware. - - - Bonding Options - ~~~~~~~~~~~~~~~ - Bonding specific options can be set using the the IFOPTS[x]="" paramter (which - takes a pipe (|) delimited list of options) for the interface being - configured. The following are the most useful options (but not an exhaustive - list - see "Further Reading" below for more information) which can be set: - lacp_rate This option specifies the rate at which the host will - ask the switch to transmit LACPDU packets in 802.3ad - mode. Possible values are: - slow Transmit LACPDUs every 30 seconds. - fast Transmit LACPDUs every 1 second. - The default is slow, but fast is recommended for rapid - recovery after a physical link failure. - miimon Specifies the MII link monitoring frequency in - milliseconds. This determines how often the link state - of each physical (slaved) interface is checked for link - failures. A value of zero disables MII link monitoring, - but this is NOT advised. A value of 100 is a good - starting point. The default value is 0, so be sure to - set this option with ALL bonding modes. - primary The physical (slave) interface (eth0, eth1, etc) which - is to be used as the primary interface. The specified - interface will always be the active slave while it is - available. Only when the primary interface is off-line - will alternate interfaces be used. This is useful when - one interface is preferred over another (e.g. when one - interface has higher throughput than another). This - option is only valid for "active-backup", "balance-tlb", - and "balance-alb" bonding modes. - xmit_hash_policy Selects the transmit hash policy to use for interface - selection in "balance-xor", "802.3ad", and "balance-tlb" - bonding modes. Possible values are: - layer2 Use eXclusive OR (XOR) of source and - destination MAC addresses and packet - type ID fields to generate the hash. - This algorithm will place all traffic - to a particular destination on the - same phydivsl (slave) interface. - layer2+3 Use a combination of layer2 and - layer3 protocol information (MAC - addresses and IP addresses) to - generate the hash. This algorithm - will place all traffic to a particular - destination on the same physical - (slave) interface. This policy is - intended to provide a more balanced - distribution of traffic than layer2 - alone. - layer3+4 This policy uses upper layer protocol - information, when available, to - generate the hash. This allows for - traffic to a particular destination to - span multiple physical (slave) - interfaces, although a single - connection will not span multiple - slaves. - The default value is layer2. Additional (lesser used) - policies are available - see the "Further Reading" - section below for further details. - - - Caveats - ~~~~~~~ - * The IFOPTS[x]="" parameter should always include the 'miimon' option - not - using this option will result in network degradation. - * In "active-backup" mode, the "primary" option should also always be - supplied. - * When using "802.3ad" mode, set "lacp_rate fast" for faster recovery from an - interface failure. In other modes, the 'xmit_hash_policy' should be set. - - - Examples - ~~~~~~~~ - FIXME: Add examples. - - - Further Reading - ~~~~~~~~~~~~~~~ - Full documentation of the bonding layer is available in the kernel source - documentation at: /usr/src/linux/Documentation/networking/bonding.txt. - - -VLANs (a.k.a, 802.1q) ---------------------- - Overview - ~~~~~~~~ - Virtual LANs (VLANs) allow the segmentation of physical networks into - multiple, isolated, private virtual networks, whilst using shared network - switches and hardware. - - VLANs work by applying tags to network frames to form virtual private LANs. - In this way, VLANs can keep network applications separate despite being - connected to the same physical network, and without requiring multiple sets of - cabling and networking devices to be deployed. - - In essence, a VLAN is a collection of devices or network hosts that - communicate with one another as if they make up a single LAN, but utilising - shared network hardware. - - Because VLAN frames are tagged with a VLAN ID, it is possible to 'cherry-pick' - those frames from the network by use of a VLAN interface on the host. - - Slackware now allows configuration of such interfaces in order to allow a host - to join a specific VLAN or VLANs. The guided deployment in 'netconfig' has - been updated to support the creation of such VLAN interfaces. - - The configuration in rc.inet1.conf for VLANs is a simple modification of the - existing support for declaration of a network interface using the standard - Slackware IFNAME[x] parameter. As shown in the examples below, VLANs - interfaces can be built on top on top of regular, physical, interfaces, or on - top of a bond interface to allow for link aggregation. - - The new IFOPT[x] generic interface options parameter can be used to customise - the usage and configuration of the VLAN interfaces, but is not required in a - normal configuration setting. - - - Exposing VLANs - ~~~~~~~~~~~~~~ - Configuring VLAN interfaces utilises the standard Slackware networking - configuration syntax in rc.inet1.conf; with setting up an interface as simple - as changing the IFNAME[x]="" parameter. - - VLAN interfaces can be configured quite simply in rc.inet1.conf, in the - standard Slackware way of defining an interface. The key to the configuration - is to use the correct IFNAME[x]="" parameter for the underlying physical (or - bond) interface and the tagged VLAN ID that should be exposed. For example: - IFNAME[0]="eth0.10" - IFOPTS[0]="" - IPADDRS[0]="192.168.10.1/24" - - The VLAN ID is taken from the full interface name, as set in the IFNAME[x] - parameter which is comprised of the underlying physical (or bond) interface - name, a period (.) and the VLAN ID to expose. The above example would use the - physical interface 'eth0', and expose the VLAN with ID 10, and configure the - interface with the IPv4 address 192.168.10.1 with a mask of 24. - - IFOPTS[x]="" is a pipe (|) delimited list of VLAN kernel module specific - settings to be applied to the interface. The ip-link(8) man page contains - details of exactly what settings can be used with this option (search for - "VLAN Type Support"). For example: - IFOPTS[x]="protocol 802.1ad | reorder_hdr off" - Under normal circumstances, where a standard VLAN interface is required, no - options need be supplied. - - - Examples - ~~~~~~~~ - FIXME: Add examples. - - -Bridges -------- - - -Wireless (WiFi) Network Interfaces ----------------------------------- - - -TUN/TAP -------- - - -Advanced networking configuration ---------------------------------- -(stacking interface configs - bond, then VLAN, then bridge) - - It is also possible to use a bond as the underlying interface, which allows - link aggregated VLAN interfaces to be created for network redundancy. For - example: - IFNAME[0]="bond0" - BONDNICS[0]="eth0 eth1" - BONDMODE[0]="active-backup" - IFOPTS[0]="miimon 100 | primary eth0" - IFNAME[1]="bond0.5" - IFNAME[2]="br0" - BRNICS[2]="bond0.5" - IPADDRS[2]="192.168.5.10/24" - IP6ADDRS[2]="a:b:c:d::1/64" - Would create a bond interface using the eth0 and eth1 physical ethernet - interfaces, in an "active-backup" redundancy configuration with the primary - interface being "eth0", exposing VLAN ID 5 and setting an IPv4 address of - "192.168.5.10" mask "24", plus an IPv6 address of "a:b:c:d::1" prefix "64" - for the interface. - - -General Caveats ---------------- - - The network interface definitions are stored in variable arrays. The bash shell has no facilities to retrieve the largest array index used. There- - fore, the rc.inet1 script makes the assumption that array indexes stay below the value of 6. Effectively this means that you can configure up to 6 - network interfaces in rc.inet1.conf by default. - - If you want to configure more than six network interfaces, you will have to edit the file /etc/rc.d/rc.inet1.conf and change the value `6' in the - line: - #MAXNICS="6" - (at the very bottom of the file) to a value that is larger than the largest index value you use, and uncomment the line. - - The /etc/rc.d/rc.wireless script is not meant to be run on its own by the user! - - -rc.inet1 does not keep a record of how an interface was configured. If the -interface config is changed in rc.inet1.conf from, say, DHCP to static IP, -restarting networking may fail because the previous type of interface config -cannot be stopped (because its type is unknown). In this instance, it is easier -to reboot to start from fresh. However, if reboot is not possible, it may be -required to bring the interface down manually (either by deconfiguring the IPs, -or killing dhcpcd) before trying to restart the interface. - |