Supplemental Linux® From Scratch - Version #2d4c

Chapter 2. General Libraries

libunbound from Unbound-1.25.1

Introduction to libunbound

The libunbound library from the Unbound package provides an API for validating, recursing, and caching DNS addresses. Unbound can provide issues with Systemd, although some packages require the library. BLFS has removed the package from the Systemd edition, leaving packages that need it in the dark. This provides the component that packages need. The daemon itself shouldn't be needed.

Additional Downloads

libunbound Dependencies

Optional

libevent and Nettle

Installation of libunbound

Make the package compatible with OpenSSL-4 by applying a patch: 

patch -Np1 -i ../unbound-1.25.1-openssl4-1.patch

Install libunbound by running the following commands: 

CFLAGS+=" -I/usr/include/nss"  \
CFLAGS+=" -I/usr/include/nspr" \
./configure --prefix=/usr      \
            --sysconfdir=/etc  \
            --disable-static  &&

make lib &&
make unbound-anchor

Now, as the root user: 

make install-lib &&
install -vDm755 .libs/unbound-anchor -t /usr/bin/ &&
install -vdm755 /etc/unbound &&
unbound-anchor

Command Explanations

--with-libevent: This option enables libevent support, which allows for the use of large outgoing port ranges.

Contents

Installed Programs: unbound-anchor
Installed Library: libunbound
Installed Directories: None

Short Descriptions

unbound-anchor

anchors unbound for DNS and certificate validation

libunbound

provides API functions to validate, recurse, and cache DNS addresses