MacPortsのautoconfでインストールができなかった

具体的なエラーは以下の通り

$ sudo port install autoconf
--->  Computing dependencies for autoconf
--->  Fetching archive for autoconf
--->  Attempting to fetch autoconf-2.69_5.darwin_17.noarch.tbz2 from http://kmq.jp.packages.macports.org/autoconf
--->  Attempting to fetch autoconf-2.69_5.darwin_17.noarch.tbz2.rmd160 from http://kmq.jp.packages.macports.org/autoconf
Warning: Failed to verify signature for archive!
Error: Failed to archivefetch autoconf: version @2.69_5
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_autoconf/autoconf/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
Error: Processing of port autoconf failed

シェルの環境変数をリロードしたら解決した。

$ source ~/.bashrc