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Posted to notifications@shardingsphere.apache.org by zh...@apache.org on 2020/07/23 16:18:54 UTC

[shardingsphere-elasticjob] branch master updated: translate faq index. (#1262)

This is an automated email from the ASF dual-hosted git repository.

zhangliang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/shardingsphere-elasticjob.git


The following commit(s) were added to refs/heads/master by this push:
     new 0770382  translate faq index. (#1262)
0770382 is described below

commit 0770382a3306bd0a2003a223977fd569381458b4
Author: Zonglei Dong <do...@apache.org>
AuthorDate: Fri Jul 24 00:18:46 2020 +0800

    translate faq index. (#1262)
---
 docs/content/faq/_index.en.md | 83 ++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 82 insertions(+), 1 deletion(-)

diff --git a/docs/content/faq/_index.en.md b/docs/content/faq/_index.en.md
index 44f168f..90ba338 100644
--- a/docs/content/faq/_index.en.md
+++ b/docs/content/faq/_index.en.md
@@ -5,4 +5,85 @@ weight = 8
 chapter = true
 +++
 
-TODO
+## 1. Why do some compiling errors appear?
+
+Answer:
+
+`ElasticJob` uses `lombok` to enable minimal coding. For more details about using and installment, please refer to the official website of [lombok](https://projectlombok.org/download.html).
+
+## 2. Does ElasticJob support dynamically adding jobs?
+
+Answer:
+
+For the concept of dynamically adding job, everyone has a different understanding.
+
+`ElasticJob-Lite` is provided in jar package, which is started by developers or operation. When the job is started, it will automatically register job information to the registry center, and the registry center will perform distributed coordination, so there is no need to manually add job information in the registry center.
+However, registry center has no affiliation with the job server, can't control the distribution of single-point jobs to other job machines, and also can't start the job of remote server.
+`ElasticJob-Lite` doesn't support ssh secret management and other functions.
+
+`ElasticJob-Cloud` is a `mesos` framework, and `mesos` is responsible for job starting and distribution.
+But you need to package the job and upload it, and call the `REST API` provided by `ElasticJob-Cloud` to write job information into the registry center.
+Packaging and uploading job are the deployment system's functions, `ElasticJob-Cloud` does not support it.
+
+In summary, `ElasticJob` has supported basic dynamically adding jobs, but it can't be fully automated.
+
+## 3. Why is the job configuration modified in the code or Spring XML file, but the registry center is not updated?
+
+Answer:
+
+`ElasticJob-Lite` adopts a decentralized design. If the configuration of each client is inconsistent and is not controlled, the configuration of the client which is last started will be the final configuration of the registry center.
+
+`ElasticJob-Lite` proposes the concept of `overwrite`, which can be configured through `JobConfiguration` or `Spring` namespace.
+`overwrite=true` indicates that the client's configuration is allowed override the registry center, and on the contrary is not allowed.
+If there is no configuration of related jobs in the registry center, regardless of whether the property of `overwrite` is configured, the client's configuration will be still written into the registry center.
+
+## 4. What happens if the job can't communicate with the registry center?
+
+Answer:
+
+In order to ensure the consistency of the job in the distributed system, once the job can't communicate with the registry center, the job will stop immediately, but the job's process will not exit.
+The purpose of this is to prevent the assignment of the shards executed by the node that has lost contact with the registry center to another node when the job is re-sharded, causing the same shard to be executed on both nodes at the same time.
+When the node resumes contact with the registry center, it will re-participate in the sharding and resume execution of the newly shard.
+
+## 5. What are the usage restrictions of `ElasticJob-Lite`?
+
+Answer:
+
+* After the job start successfully, modifying the job name is regarded as a new job, and the original job is discarded.
+
+* It will be triggered re-sharding if the server changes, or if the sharding item is modified; re-sharding will cause the running streaming job to stop after the job is executed, and this job will return to normal after the re-sharding is finished.
+
+* Enable `monitorExecution` to realize the function of distributed job idempotence (that is, the same shard will not be run on different job servers), but `monitorExecution` has a greater impact on the performance of jobs executed in a short period of time (such as second-level triggers). It is recommended to turn it off and realize idempotence by yourself.
+
+## 6. What should you do if you suspect that `ElasticJob-Lite` has a problem in a distributed environment, but it cannot be reproduced and cannot be debugged in the online environment?
+
+Answer:
+
+Distributed problems are very difficult to debug and reproduce. For this reason, `ElasticJob-Lite` provides the `dump` command.
+
+If you suspect a problem in some scenarios, you can refer to the [dump](/en/user-manual/dump/) document to submit the job runtime information to the community.
+`ElasticJob` has filtered sensitive information such as `IP`, and the dump file can be safely transmitted on the Internet.
+
+## 7. What are the usage restrictions of `ElasticJob-Cloud`?
+
+Answer:
+
+* After the job start successfully, modifying the job name is regarded as a new job, and the original job is discarded.
+
+## 8. When add a task in the `ElasticJob-Cloud`, why does it remain in the ready state, but doesn't start?
+
+Answer:
+
+The task will start when `mesos` has a separate `agent` that can provide the required resources, otherwise it will wait until there are enough resources.
+
+## 9. Why can't the Console page display normally?
+
+Answer:
+
+Make sure that the `Web Console`'s version is consistent with `ElasticJob`, otherwise it will become unavailable.
+
+## 10. Why is the job state shard to be adjusted in the Console?
+
+Answer:
+
+Shard to be adjusted indicates the state when the job has started but has not yet obtained the shard.