docs: fix Docker 1C2D example path and pgxc configuration filename

docs/guide/15-docker-deploy.en.md

@@ -12,7 +12,20 @@ cd ${SOURCECODE_PATH}/docker
 
 Commands above will build `opentenbasebase` and `opentenbase` images.
 
+Replace `SOURCECODE_PATH` with the path of your local clone of this repository, for example `/data/opentenbase/OpenTenBase`.
+
 ## 2.Start the example service and enter the CN contaioner
+
+> **Note**: the directory `${SOURCECODE_PATH}/example/1c_2d_cluster` no longer exists on the current `master` branch, so the commands below cannot be run as written.
+> Its `docker-compose.yaml`, `README` and `pgxc_conf/` were removed together with the whole `example/` tree, by commit
+> [`aca7e2c`](https://github.com/OpenTenBase/OpenTenBase/commit/aca7e2c34a25e1480548a20dc7462612fb8a17f7) ("Update basecode version from 2.6.0 to 5.0.0") in the OpenTenBase repository.
+> The only part still present in that repository is the image build path used in step 1 (`docker/buildImage.sh`).
+>
+> The cluster configuration template used by this example is still published in this repository:
+> <https://github.com/OpenTenBase/docs/blob/main/docs/guide/pgxc_ctl_double.conf>.
+> If you need the removed `docker-compose.yaml`, it can be retrieved from the revision just before the deletion:
+> <https://github.com/OpenTenBase/OpenTenBase/tree/efc01b0c079f73900ab2a199c90ff04fe3ad6435/example/1c_2d_cluster> (historical file, no longer maintained).
+
 ```shell
 cd ${SOURCECODE_PATH}/example/1c_2d_cluster
 docker-compose up -d
@@ -39,12 +52,17 @@ cp ~/pgxc_conf/pgxc_ctl.conf ~/pgxc_ctl
 Use `pgxc_ctl` for deployment. Avoid using commands like `ls` or `echo` after entering `pgxc_ctl`.
 ```shell
 pgxc_ctl                                # This step will enter --home location, which is by default /home/$USER/pgxc_ctl. Type exit to exit or Ctrl + D
-deploy all                              # This will use pgxc.conf located in /home/$USER/pgxc_ctl/pgxc.conf for deployment
+deploy all                              # This will use /home/$USER/pgxc_ctl/pgxc_ctl.conf for deployment
 init all
 
 exit
 ```
 
+The configuration file name read by `pgxc_ctl` is fixed to `pgxc_ctl.conf`, located in the directory given by `--home`
+(`$HOME/pgxc_ctl` by default); see `contrib/pgxc_ctl/pgxc_ctl.h` (`DEFAULT_CONF_FILE_NAME`) and
+`contrib/pgxc_ctl/pgxc_ctl.c` (`build_configuration_path()`) in the OpenTenBase repository.
+The file copied in step 4 therefore **must not be renamed**; `pgxc.conf` is the configuration file of a different,
+unrelated tool, `pgxc_ddl`.
 
 ## 5.Connect OpenTenbase using psql
 

docs/guide/15-docker-deploy.md

@@ -12,7 +12,20 @@ cd ${SOURCECODE_PATH}/docker
 
 上述指令会构建`opentenbasebase`和 `opentenbase`两个镜像。
 
+其中 `SOURCECODE_PATH` 请替换为本仓库在本机的克隆路径，例如 `/data/opentenbase/OpenTenBase`。
+
 ## 2.启动 example 服务，进入 opentenbaseCN 容器
+
+> **注意**：`${SOURCECODE_PATH}/example/1c_2d_cluster` 目录在当前 `master` 分支上已不存在，因此下面这段命令目前无法执行。
+> 该目录下的 `docker-compose.yaml`、`README` 和 `pgxc_conf/` 已随整个 `example/` 目录，在 OpenTenBase 仓库的提交
+> [`aca7e2c`](https://github.com/OpenTenBase/OpenTenBase/commit/aca7e2c34a25e1480548a20dc7462612fb8a17f7)（"Update basecode version from 2.6.0 to 5.0.0"）中被移除。
+> 目前仓库里保留的只有第 1 步的镜像构建路径（`docker/buildImage.sh`）。
+>
+> 本次示例使用的集群配置模板仍发布在本仓库中：
+> <https://github.com/OpenTenBase/docs/blob/main/docs/guide/pgxc_ctl_double.conf>。
+> 如果需要被移除的 `docker-compose.yaml`，可从删除前的历史版本获取：
+> <https://github.com/OpenTenBase/OpenTenBase/tree/efc01b0c079f73900ab2a199c90ff04fe3ad6435/example/1c_2d_cluster>（历史文件，已不再维护）。
+
 ```shell
 cd ${SOURCECODE_PATH}/example/1c_2d_cluster
 docker-compose up -d
@@ -39,12 +52,16 @@ cp ~/pgxc_conf/pgxc_ctl.conf ~/pgxc_ctl
 使用 `pgxc_ctl`  进行部署，使用`pgxc_ctl`之后，不要敲 `ls` ,`echo` 这种命令。
 ```shell
 pgxc_ctl                                # 这一步会进入 --home 位置，默认是/home/$USER/pgxc_ctl, 使用exit退出，或者ctrl + D
-deploy all                              # 会使用/home/$USER/pgxc_ctl/pgxc.conf 这个配置文件
+deploy all                              # 会使用 /home/$USER/pgxc_ctl/pgxc_ctl.conf 这个配置文件
 init all
 
 exit
 ```
 
+`pgxc_ctl` 读取的配置文件名固定为 `pgxc_ctl.conf`，位置为 `--home` 指定的目录（默认 `$HOME/pgxc_ctl`），
+可参考 OpenTenBase 仓库中的 `contrib/pgxc_ctl/pgxc_ctl.h`（`DEFAULT_CONF_FILE_NAME`）和
+`contrib/pgxc_ctl/pgxc_ctl.c`（`build_configuration_path()`）。
+因此第 4 步复制过去的文件**无需改名**；`pgxc.conf` 是另一个独立工具 `pgxc_ddl` 的配置文件，请不要与它混淆。
 
 ## 5.使用psql连接OpenTenbase