Supplemental Linux® From Scratch - Version #418f

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

Recommended

NSS and NSPR

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        \
            --with-nss              \
            --with-libunbound-only &&
make

Now, as the root user: 

make install

Command Explanations

--with-nss: This ensures libunbound is built with NSS.

--with-libunbound-only: This ensures only the library is built.

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

Contents

Installed Programs: None
Installed Library: libunbound
Installed Directories: None

Short Descriptions

libunbound

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