Dockerfile rsyslog

Question

我已经实现了一个 dockerfile 来拥有一个使用 rsyslog 记录日志的后缀，但它在运行时会引发错误。

输出错误：

tail: cannot open '/var/log/mail.log' for reading: No such file or directory
tail: no files remaining

这是我的 Dockerfile：

FROM ubuntu:16.04

RUN apt-get update && apt-get install -y libsasl2-modules postfix rsyslog && rm -rf /var/lib/apt/lists/*

COPY main.cf /etc/postfix/
COPY ca-certificates.crt /etc/ssl/certs/

EXPOSE 25

CMD service rsyslog start && service postfix start && tail -f /var/log/mail.log

任何帮助将不胜感激。

Answer 1

删除这些行：

RUN touch /dev/xconsole && chgrp syslog /dev/xconsole && chmod 664 /dev/xconsole
RUN service rsyslog restart

并首先更新CMD 以启动rsyslog：

CMD service rsyslog start && service postfix start && tail -f /var/log/mail.log

因为RUN 在镜像构建期间执行命令，而CMD 在运行容器中执行命令，您需要在运行容器中运行 rsyslogd。

结果 Dockerfile 可能如下所示：

FROM ubuntu:16.04

RUN apt-get update && apt-get install -y libsasl2-modules postfix rsyslog; \
    rm -rf /var/lib/apt/lists/*
RUN echo "[smtp.gmail.com]:587 email@gmail.com:password" > /etc/postfix/sasl_passwd; \
    postmap /etc/postfix/sasl_passwd; \
    sed -i '/relayhost*/c\relayhost = [smtp.gmail.com]:587' /etc/postfix/main.cf; \
    sed -i '/smtp_sasl_auth_enable*/c\smtp_sasl_auth_enable = yes' /etc/postfix/main.cf; \
    sed -i '/smtp_sasl_security_options*/c\smtp_sasl_security_options = noanonymous' /etc/postfix/main.cf; \
    sed -i '/smtp_sasl_password_maps*/c\smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd' /etc/postfix/main.cf; \
    sed -i '/smtp_tls_security_level*/c\smtp_tls_security_level = encrypt' /etc/postfix/main.cf; \
    sed -i '/smtp_tls_CAfile*/c\smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt' /etc/postfix/main.cf

EXPOSE 587

CMD service rsyslog start && service postfix start && tail -f /var/log/mail.log

构建它：docker build -t postfix -f Dockerfile.postfix .

当你运行它时：docker run -it --rm --name postfix postfix

...然后你有邮件登录控制台：

 * Starting enhanced syslogd rsyslogd                                    [ OK ] 
 * Starting Postfix Mail Transport Agent postfix                                                                                                                                                                   postfix: Postfix is running with backwards-compatible default settings
postfix: See http://www.postfix.org/COMPATIBILITY_README.html for details
postfix: To disable backwards compatibility use "postconf compatibility_level=2" and "postfix reload"
                                                                                                                                                                                                            [ OK ]
Sep 26 20:11:01 6009a2e3d206 postfix[111]: Postfix is running with backwards-compatible default settings
Sep 26 20:11:01 6009a2e3d206 postfix[111]: See http://www.postfix.org/COMPATIBILITY_README.html for details
Sep 26 20:11:01 6009a2e3d206 postfix[111]: To disable backwards compatibility use "postconf compatibility_level=2" and "postfix reload"
Sep 26 20:11:01 6009a2e3d206 postfix/master[156]: daemon started -- version 3.1.0, configuration /etc/postfix
Sep 26 20:11:01 6009a2e3d206 postfix/pickup[159]: error: open file /etc/mailname: No such file or directory
Sep 26 20:11:01 6009a2e3d206 postfix/qmgr[160]: error: open file /etc/mailname: No such file or directory

您还可以使用 exec 命令检查邮件日志：docker exec postfix cat /var/log/mail.log。这在将容器作为守护进程运行时会很有帮助（-d 标志）。

---

关于rsyslogd-2039: Could not open output pipe 错误 - 您可以忽略它。

但如果你不想忽略它，你可以更新你的CMD 并像这样：

CMD touch /dev/xconsole && chgrp syslog /dev/xconsole && chmod 664 /dev/xconsole && service rsyslog start && service postfix start && tail -f /var/log/mail.log