CentOS 7

This document describes installation from source. If you want to build an RPM, see Packaging Red Hat.

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 protobuf-c-devel

Note

The libunwind library is optional but highly recommended, as it improves backtraces printed for crashes and debugging. However, if it is not available for some reason, it can simply be left out without any loss of functionality.

FRR depends on the libyang library to provide YANG/NETCONF support. Some distributions do not offer a libyang package or offer old versions. Therefore we provide two options below to install this library.

Note

libyang version 2.1.128 or newer is required to build FRR.

libyang version 3 is recommended, with support added in FRR 10.2.

libyang version 4 is not preferred to version 3. V4 has placed restrictions on the use of the internal binary encoding format (LYD_LYB). As a result internal FRR messages have to fall back to using either JSON or XML encoding.

libyang version 5 restores support for using the binary encoding that was removed in version 4, however, a few minor changes in FRR are required before it will again be taken advantage of.

Option 1: Binary Install

The FRR project builds some binary libyang packages.

RPM packages are available in our RPM repository.

DEB packages are available in our DEB repository.

Note

The libyang development packages need to be installed in addition to the libyang core package in order to build FRR successfully. Make sure to download and install those from the link above alongside the binary packages.

Depending on your platform, you may also need to install the PCRE development package. Typically this is libpcre2-dev or pcre2-devel.

Option 2: Source Install

Note

Ensure that the libyang build requirements are met before continuing. Usually this entails installing cmake and libpcre2-dev or pcre2-devel.

git clone https://github.com/CESNET/libyang.git
cd libyang
git checkout v3.13.6
mkdir build; cd build
cmake --install-prefix /usr \
      -D CMAKE_BUILD_TYPE:String="Release" ..
make
sudo make install

Note

The git tag used above is just a suggestion, not a requirement. Feel free to change it to newer or older version 3 release tags if you wish.

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 \
    --libdir=/usr/lib/frr \
    --libexecdir=/usr/lib/frr \
    --with-moduledir=/usr/lib/frr/modules \
    --enable-snmp \
    --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
sudo install -m 640 -o frr -g frr tools/etc/frr/support_bundle_commands.conf /etc/frr/support_bundle_commands.conf

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