CentOS 7
========================================

This document describes installation from source. If you want to build an RPM,
see :ref:`packaging-redhat`.

CentOS 7 restrictions:
----------------------

-  MPLS is not supported on ``CentOS 7`` with default kernel. MPLS
   requires Linux Kernel 4.5 or higher (LDP can be built, but may have
   limited use without MPLS)

Install required packages
-------------------------

Add packages:

::

    sudo yum install git autoconf automake libtool make \
      readline-devel texinfo net-snmp-devel groff pkgconfig \
      json-c-devel pam-devel bison flex pytest c-ares-devel \
      python-devel python-sphinx libcap-devel \
      elfutils-libelf-devel libunwind-devel

.. include:: building-libunwind-note.rst

.. include:: building-libyang.rst

Get FRR, compile it and install it (from Git)
---------------------------------------------

**This assumes you want to build and install FRR from source and not
using any packages**

Add frr groups and user
^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo groupadd -g 92 frr
    sudo groupadd -r -g 85 frrvty
    sudo useradd -u 92 -g 92 -M -r -G frrvty -s /sbin/nologin \
      -c "FRR FRRouting suite" -d /var/run/frr frr

Download Source, configure and compile it
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

(You may prefer different options on configure statement. These are just
an example.)

::

    git clone https://github.com/frrouting/frr.git frr
    cd frr
    ./bootstrap.sh
    ./configure \
        --bindir=/usr/bin \
        --sbindir=/usr/lib/frr \
        --sysconfdir=/etc/frr \
        --libdir=/usr/lib/frr \
        --libexecdir=/usr/lib/frr \
        --localstatedir=/var/run/frr \
        --with-moduledir=/usr/lib/frr/modules \
        --enable-snmp=agentx \
        --enable-multipath=64 \
        --enable-user=frr \
        --enable-group=frr \
        --enable-vty-group=frrvty \
        --disable-ldpd \
        --enable-fpm \
        --with-pkg-git-version \
        --with-pkg-extra-version=-MyOwnFRRVersion \
	SPHINXBUILD=/usr/bin/sphinx-build
    make
    make check
    sudo make install

Create empty FRR configuration files
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo mkdir /var/log/frr
    sudo mkdir /etc/frr
    sudo touch /etc/frr/zebra.conf
    sudo touch /etc/frr/bgpd.conf
    sudo touch /etc/frr/ospfd.conf
    sudo touch /etc/frr/ospf6d.conf
    sudo touch /etc/frr/isisd.conf
    sudo touch /etc/frr/ripd.conf
    sudo touch /etc/frr/ripngd.conf
    sudo touch /etc/frr/pimd.conf
    sudo touch /etc/frr/nhrpd.conf
    sudo touch /etc/frr/eigrpd.conf
    sudo touch /etc/frr/babeld.conf
    sudo chown -R frr:frr /etc/frr/
    sudo touch /etc/frr/vtysh.conf
    sudo chown frr:frrvty /etc/frr/vtysh.conf
    sudo chmod 640 /etc/frr/*.conf

Install daemon config file
^^^^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo install -p -m 644 tools/etc/frr/daemons /etc/frr/
    sudo chown frr:frr /etc/frr/daemons

Edit /etc/frr/daemons as needed to select the required daemons
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Look for the section with ``watchfrr_enable=...`` and ``zebra=...`` etc.
Enable the daemons as required by changing the value to ``yes``

Enable IP & IPv6 forwarding
^^^^^^^^^^^^^^^^^^^^^^^^^^^

Create a new file ``/etc/sysctl.d/90-routing-sysctl.conf`` with the
following content:

::

    # Sysctl for routing
    #
    # Routing: We need to forward packets
    net.ipv4.conf.all.forwarding=1
    net.ipv6.conf.all.forwarding=1

Load the modified sysctl's on the system:

::

    sudo sysctl -p /etc/sysctl.d/90-routing-sysctl.conf

Install frr Service
^^^^^^^^^^^^^^^^^^^

::

    sudo install -p -m 644 tools/frr.service /usr/lib/systemd/system/frr.service

Register the systemd files
^^^^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo systemctl preset frr.service

Enable required frr at startup
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo systemctl enable frr

Reboot or start FRR manually
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

::

    sudo systemctl start frr