gem install pgすると失敗する。yum install postgresql-develでも解消しない。


`gem install pg`すると以下のエラーが出ます。  
実行しているのはEC2でOSはAmazon Linuxです。

[code]

    $ gem install pg -v '0.20.0'
    Building native extensions.  This could take a while...
    ERROR:  Error installing pg:
        ERROR: Failed to build gem native extension.
    current directory: /home/ec2-user/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/pg-0.20.0/ext
    /home/ec2-user/.rbenv/versions/2.4.1/bin/ruby -r ./siteconf20180206-457-e5bx4w.rb extconf.rb
    checking for pg_config... yes
    Using config values from /usr/bin/pg_config
    checking for libpq-fe.h... no
    Can't find the 'libpq-fe.h header
    *** extconf.rb failed ***
    Could not create Makefile due to some reason, probably lack of necessary
    libraries and/or headers.  Check the mkmf.log file for more details.  You may
    need configuration options.
    Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=/home/ec2-user/.rbenv/versions/2.4.1/bin/$(RUBY_BASE_NAME)
        --with-pg
        --without-pg
        --enable-windows-cross
        --disable-windows-cross
        --with-pg-config
        --without-pg-config
        --with-pg_config
        --without-pg_config
        --with-pg-dir
        --without-pg-dir
        --with-pg-include
        --without-pg-include=${pg-dir}/include
        --with-pg-lib
        --without-pg-lib=${pg-dir}/lib
    
    To see why this extension failed to compile, please check the mkmf.log which can be found here:
    
      /home/ec2-user/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0-static/pg-0.20.0/mkmf.log
    
    extconf failed, exit code 1
    
    Gem files will remain installed in /home/ec2-user/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/pg-0.20.0 for inspection.
    Results logged to /home/ec2-user/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/extensions/x86_64-linux/2.4.0-static/pg-0.20.0/gem_make.out
    
[/code]

以下を実行しましたが、エラー内容は変わりませんでした。

[code]

    $ sudo yum install postgresql-devel
    
[/code]

また、psqlの設定ファイルは以下の通りです。

[code]

    $ ls -l /usr/bin/pg*
    lrwxrwxrwx 1 root root     35  2月  6 08:47 /usr/bin/pg_archivecleanup -> /etc/alternatives/pg_archivecleanup
    lrwxrwxrwx 1 root root     45  2月  6 08:36 /usr/bin/pg_archivecleanup96 -> ../../usr/lib64/pgsql96/bin/pg_archivecleanup
    lrwxrwxrwx 1 root root     31  2月  6 08:47 /usr/bin/pg_basebackup -> /etc/alternatives/pg_basebackup
    lrwxrwxrwx 1 root root     41  2月  6 08:36 /usr/bin/pg_basebackup96 -> ../../usr/lib64/pgsql96/bin/pg_basebackup
    lrwxrwxrwx 1 root root     27  2月  6 08:47 /usr/bin/pg_config -> /etc/alternatives/pg_config
    lrwxrwxrwx 1 root root     37  2月  6 08:47 /usr/bin/pg_config92 -> ../../usr/lib64/pgsql92/bin/pg_config
    lrwxrwxrwx 1 root root     37  2月  6 08:36 /usr/bin/pg_config96 -> ../../usr/lib64/pgsql96/bin/pg_config
    lrwxrwxrwx 1 root root     32  2月  6 08:47 /usr/bin/pg_controldata -> /etc/alternatives/pg_controldata
    lrwxrwxrwx 1 root root     42  2月  6 08:36 /usr/bin/pg_controldata96 -> ../../usr/lib64/pgsql96/bin/pg_controldata
    lrwxrwxrwx 1 root root     24  2月  6 08:47 /usr/bin/pg_ctl -> /etc/alternatives/pg_ctl
    lrwxrwxrwx 1 root root     34  2月  6 08:36 /usr/bin/pg_ctl96 -> ../../usr/lib64/pgsql96/bin/pg_ctl
    lrwxrwxrwx 1 root root     25  2月  6 08:47 /usr/bin/pg_dump -> /etc/alternatives/pg_dump
    lrwxrwxrwx 1 root root     35  2月  6 08:47 /usr/bin/pg_dump92 -> ../../usr/lib64/pgsql92/bin/pg_dump
    lrwxrwxrwx 1 root root     35  2月  6 08:36 /usr/bin/pg_dump96 -> ../../usr/lib64/pgsql96/bin/pg_dump
    lrwxrwxrwx 1 root root     28  2月  6 08:47 /usr/bin/pg_dumpall -> /etc/alternatives/pg_dumpall
    lrwxrwxrwx 1 root root     38  2月  6 08:47 /usr/bin/pg_dumpall92 -> ../../usr/lib64/pgsql92/bin/pg_dumpall
    lrwxrwxrwx 1 root root     38  2月  6 08:36 /usr/bin/pg_dumpall96 -> ../../usr/lib64/pgsql96/bin/pg_dumpall
    lrwxrwxrwx 1 root root     28  2月  6 08:47 /usr/bin/pg_isready -> /etc/alternatives/pg_isready
    lrwxrwxrwx 1 root root     38  2月  6 08:36 /usr/bin/pg_isready96 -> ../../usr/lib64/pgsql96/bin/pg_isready
    lrwxrwxrwx 1 root root     32  2月  6 08:47 /usr/bin/pg_receivexlog -> /etc/alternatives/pg_receivexlog
    lrwxrwxrwx 1 root root     42  2月  6 08:36 /usr/bin/pg_receivexlog96 -> ../../usr/lib64/pgsql96/bin/pg_receivexlog
    lrwxrwxrwx 1 root root     32  2月  6 08:47 /usr/bin/pg_recvlogical -> /etc/alternatives/pg_recvlogical
    lrwxrwxrwx 1 root root     42  2月  6 08:36 /usr/bin/pg_recvlogical96 -> ../../usr/lib64/pgsql96/bin/pg_recvlogical
    lrwxrwxrwx 1 root root     30  2月  6 08:47 /usr/bin/pg_resetxlog -> /etc/alternatives/pg_resetxlog
    lrwxrwxrwx 1 root root     40  2月  6 08:36 /usr/bin/pg_resetxlog96 -> ../../usr/lib64/pgsql96/bin/pg_resetxlog
    lrwxrwxrwx 1 root root     28  2月  6 08:47 /usr/bin/pg_restore -> /etc/alternatives/pg_restore
    lrwxrwxrwx 1 root root     38  2月  6 08:47 /usr/bin/pg_restore92 -> ../../usr/lib64/pgsql92/bin/pg_restore
    lrwxrwxrwx 1 root root     38  2月  6 08:36 /usr/bin/pg_restore96 -> ../../usr/lib64/pgsql96/bin/pg_restore
    lrwxrwxrwx 1 root root     27  2月  6 08:47 /usr/bin/pg_rewind -> /etc/alternatives/pg_rewind
    lrwxrwxrwx 1 root root     37  2月  6 08:36 /usr/bin/pg_rewind96 -> ../../usr/lib64/pgsql96/bin/pg_rewind
    lrwxrwxrwx 1 root root     28  2月  6 08:47 /usr/bin/pg_standby -> /etc/alternatives/pg_standby
    lrwxrwxrwx 1 root root     38  2月  6 08:36 /usr/bin/pg_standby96 -> ../../usr/lib64/pgsql96/bin/pg_standby
    lrwxrwxrwx 1 root root     31  2月  6 08:47 /usr/bin/pg_test_fsync -> /etc/alternatives/pg_test_fsync
    lrwxrwxrwx 1 root root     41  2月  6 08:36 /usr/bin/pg_test_fsync96 -> ../../usr/lib64/pgsql96/bin/pg_test_fsync
    lrwxrwxrwx 1 root root     32  2月  6 08:47 /usr/bin/pg_test_timing -> /etc/alternatives/pg_test_timing
    lrwxrwxrwx 1 root root     42  2月  6 08:36 /usr/bin/pg_test_timing96 -> ../../usr/lib64/pgsql96/bin/pg_test_timing
    lrwxrwxrwx 1 root root     29  2月  6 08:47 /usr/bin/pg_xlogdump -> /etc/alternatives/pg_xlogdump
    lrwxrwxrwx 1 root root     39  2月  6 08:36 /usr/bin/pg_xlogdump96 -> ../../usr/lib64/pgsql96/bin/pg_xlogdump
    -rwxr-xr-x 1 root root 375360 10月 14  2012 /usr/bin/pgawk
    lrwxrwxrwx 1 root root     25  2月  6 08:47 /usr/bin/pgbench -> /etc/alternatives/pgbench
    lrwxrwxrwx 1 root root     35  2月  6 08:36 /usr/bin/pgbench96 -> ../../usr/lib64/pgsql96/bin/pgbench
    -rwxr-xr-x 2 root root  15872  3月 17  2015 /usr/bin/pgrep
    
[/code]

`libpq`を含むファイルがなかったのでこれが原因なのではないかと思い、以下を実行しましたがインストールできませんでした。

[code]

    $ sudo yum install libpq-dev
    読み込んだプラグイン:priorities, update-motd, upgrade-helper
    amzn-main                                                                                           | 2.1 kB  00:00:00     
    amzn-updates                                                                                        | 2.5 kB  00:00:00     
    23 packages excluded due to repository priority protections
    パッケージ libpq-dev は利用できません。
    
[/code]

`libpq-dev`がないため`gem install pg`でエラーが起きるのでしょうか？  
上記が理由の場合どのようなコマンドでインストールできるでしょうか？  
`gem install pg`のエラーを解決したいです。

恐れ入りますが、よろしくお願いいたします。




PostgreSQLをPostgreSQLのリポジトリからインストールしたのであれば、関連するパッケージもそれに対応するものをインストールする必要があります。

postgresql96-develをインストールしてください。

