CN112671554A - Node fault processing method and related device - Google Patents

Node fault processing method and related device Download PDF

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Publication number
CN112671554A
CN112671554A CN202011357395.2A CN202011357395A CN112671554A CN 112671554 A CN112671554 A CN 112671554A CN 202011357395 A CN202011357395 A CN 202011357395A CN 112671554 A CN112671554 A CN 112671554A
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Prior art keywords
node
nfs
nfs client
auxiliary
request
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CN202011357395.2A
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Chinese (zh)
Inventor
李光辉
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Suzhou Inspur Intelligent Technology Co Ltd
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Suzhou Inspur Intelligent Technology Co Ltd
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Priority to CN202011357395.2A priority Critical patent/CN112671554A/en
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Abstract

The application discloses a node fault processing method, which comprises the following steps: after the nfs client is connected with the nfs server, the nfs client sends an available node request to the nfs server so that the nfs server can return an available node address list; determining an auxiliary node from the available node address list, and sending a registration request to the auxiliary node, so that when a main node connected with the nfs client fails, the auxiliary node sends a resource change message to the nfs client; when receiving the resource change message, the nfs client connects to a new node. Through the determined auxiliary node, when the main node fails, the auxiliary node informs the nfs client of the failure, instead of discovering the failure through tcp connection, node switching is further performed, and the efficiency of repairing after the failure is improved. The application also discloses a node fault processing device, a server and a computer readable storage medium, which have the beneficial effects.

Description

Node fault processing method and related device
Technical Field
The present application relates to the field of data storage technologies, and in particular, to a node failure processing method, a node failure processing apparatus, a server, and a computer-readable storage medium.
Background
With the continuous development of network application technology, in order to enable a user to conveniently and quickly access corresponding data, the user does not only access data in a local storage. Therefore, a Network File System (nfs) is presented, which is a UNIX presentation layer protocol and enables users to access files elsewhere on the Network just as if they were using their own computers. Specifically, nfs is an application based on a UDP (User Datagram Protocol)/IP (Internet Protocol), and is implemented mainly by using a Remote Procedure Call (RPC) mechanism, where RPC provides a set of operations for accessing Remote files that are unrelated to a machine, an operating system, and a lower layer transport Protocol. RPC uses XDR (External Data Representation) support. The XDR is a data description coding protocol independent of a machine, encodes and decodes data transmitted on the network in a format independent of any machine architecture, and supports the transmission of the data between heterogeneous systems.
The operation principle of nfs is to use a client/server architecture, which is composed of a client program and a server program. The server program provides access to the file system to other computers, a process referred to as export. When the nfs client program accesses the shared file system, it "feeds" them out of the nfs server. Files are typically transferred in units of blocks. The nfs transport protocol is used for file access and sharing communications between servers and clients, thereby enabling clients to remotely access data stored on storage devices.
In the related art, in an environment where nfs services are provided by multiple nodes of a cluster, after a single-node failure, an nfs client usually needs to wait for a tcp (Transmission Control Protocol) connection to be disconnected before discovering that an original server is disconnected, and at this time, a new node is reconnected to perform normal service. However, it takes a long time to determine the occurrence of a failure by tcp disconnection, which causes a decrease in the efficiency of failure recovery.
Therefore, how to improve the efficiency of node fault post-repair in nfs applications is a key issue that is of concern to those skilled in the art.
Disclosure of Invention
The application aims to provide a node fault processing method, a node fault processing device, a server and a computer readable storage medium.
In order to solve the above technical problem, the present application provides a node fault processing method, including:
after an nfs client is connected with an nfs server, the nfs client sends an available node request to the nfs server, so that the nfs server returns an available node address list;
determining an auxiliary node from the available node address list, and sending a registration request to the auxiliary node, so that when a main node connected with the nfs client fails, the auxiliary node sends a resource change message to the nfs client;
and when the resource change message is received, the nfs client is connected with a new node.
Optionally, the method further includes:
the nfs client sends a resource subscription request to the auxiliary node, so that the auxiliary node adds the nfs client to a subscription list of a corresponding node according to the resource subscription request, and sends a resource change message to the nfs client when the corresponding node has a resource available condition;
and connecting corresponding nodes according to the resource change message.
Optionally, the method further includes:
and the nfs client sends a subscription cancellation request to the auxiliary node so that the auxiliary node deletes the nfs client from the registration list.
Optionally, the method further includes:
and when the auxiliary node receives the registration request, recording the nfs client into a registration list, and monitoring the main node connected with the nfs client according to a preset period.
The present application further provides a node fault handling apparatus, including:
the node request module is used for sending a node request to the nfs server after the nfs client is connected with the nfs server, so that the nfs server can return a node address list;
an auxiliary node determining module, configured to determine an auxiliary node from the available node address list, and send a registration request to the auxiliary node, so that when a master node connected to the nfs client fails, the auxiliary node sends a resource change message to the nfs client;
and the node fault switching module is used for connecting the nfs client with a new node when the resource change message is received.
Optionally, the method further includes:
the resource subscription module is used for sending a resource subscription request to the auxiliary node so that the auxiliary node adds the nfs client to a subscription list of a corresponding node according to the resource subscription request, and when the corresponding node has a resource available condition, a resource change message is sent to the nfs client; and connecting corresponding nodes according to the resource change message.
Optionally, the method further includes:
and the subscription cancellation module is used for sending a subscription cancellation request to the auxiliary node by the nfs client so that the auxiliary node can delete the nfs client from a registration list.
Optionally, the auxiliary node is further configured to record the nfs client in a registration list when the auxiliary node receives the registration request, and monitor a master node connected to the nfs client according to a preset period.
The present application further provides a server, comprising:
a memory for storing a computer program;
a processor for implementing the steps of the node failure handling method as described above when executing the computer program.
The present application also provides a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of the node failure handling method as described above.
The node fault processing method provided by the application comprises the following steps: after an nfs client is connected with an nfs server, the nfs client sends an available node request to the nfs server, so that the nfs server returns an available node address list; determining an auxiliary node from the available node address list, and sending a registration request to the auxiliary node, so that when a main node connected with the nfs client fails, the auxiliary node sends a resource change message to the nfs client; and when the resource change message is received, the nfs client is connected with a new node.
Through the determined auxiliary node, when the main node fails, the auxiliary node informs the nfs client of the failure, instead of discovering the failure through tcp connection, node switching is further performed, and the efficiency of repairing after the failure is improved.
The present application further provides a node failure processing apparatus, a server, and a computer-readable storage medium, which have the above beneficial effects and are not described herein again.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a flowchart of a node fault processing method according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of a node fault handling apparatus according to an embodiment of the present application.
Detailed Description
The core of the application is to provide a node fault processing method, a node fault processing device, a server and a computer readable storage medium, through a determined auxiliary node, when a main node fails, the auxiliary node informs an nfs client of the failure, instead of finding the failure through tcp connection, node switching is further performed, and the efficiency of repairing after the failure is improved.
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
In the related art, in an environment where nfs services are provided by multiple nodes of a cluster, after a single-node failure, an nfs client usually needs to wait for tcp connection to be disconnected before discovering that the original server is disconnected, and then reconnects a new node to perform normal service. However, it takes a long time to determine the occurrence of a failure by tcp disconnection, which causes a decrease in the efficiency of failure recovery.
Therefore, according to the node fault processing method provided by the application, through the determined auxiliary node, after the main node fails, the auxiliary node informs the nfs client of the failure, instead of discovering the failure through tcp connection, node switching is further performed, and the efficiency of repairing after the failure is improved.
The following describes a node failure processing method provided by the present application, by an embodiment.
Referring to fig. 1, fig. 1 is a flowchart illustrating a node failure processing method according to an embodiment of the present disclosure.
In this embodiment, the method may include:
s101, after the nfs client-side is connected with the nfs server-side, the nfs client-side sends a request of available nodes to the nfs server-side, so that the nfs server-side returns an address list of the available nodes;
therefore, the step aims to send the available node request to the nfs server by the nfs client after the nfs client is connected with the nfs server, so that the nfs server can return the available node address list. That is, after the nfs client is normally added to the nfs service cluster, the node address list of all currently available nodes is requested from the nfs server.
Wherein, the nfs client refers to an nfs client which requests an nfs node in an nfs application environment. The nfs server is a server providing nfs application to the outside. Generally, the nfs server may be composed of a plurality of nfs nodes, and may also be managed by a unified domain name, and then the nfs client is connected to a node in the nfs server through load balancing.
The connection between the nfs client and the nfs server may be established in any connection manner provided in the prior art, which is not specifically limited herein.
S102, determining an auxiliary node from an available node address list, and sending a registration request to the auxiliary node, so that when a main node connected with an nfs client fails, the auxiliary node sends a resource change message to the nfs client;
on the basis of S101, the step aims at determining an auxiliary node from an available node address list and sending a registration request to the auxiliary node so that the auxiliary node sends a resource change message to an nfs client when a main node connected with the nfs client fails;
the nfs client in this step may determine, from the available node address list, a node with the best performance as an auxiliary node through the performance of each node, and send a registration request to the auxiliary node, so that the auxiliary node records and determines the nfs client as a corresponding client.
When the auxiliary node receives the registration request, the information of the nfs client is recorded in a local list of the auxiliary node, so that the operation condition of a main node connected with the nfs client can be monitored in real time. Further, when the main node connected to the nfs client fails, a resource change message is sent to the nfs client, so as to notify the main node connected to the nfs client that the failure occurs and to perform corresponding processing.
Further, in order to improve the performance utilization of the nfs client connection node, this embodiment may further include:
the nfs client sends a resource subscription request to the auxiliary node, so that the auxiliary node adds the nfs client to a subscription list of the corresponding node according to the resource subscription request, and sends a resource change message to the nfs client when the corresponding node has a resource available condition;
and connecting the corresponding nodes according to the resource change message.
It can be seen that, in this alternative, the mfs client may also send a further resource subscription request to the secondary node, so as to subscribe to the dynamic situation of the resource of the relevant node through the secondary node. For example, node resource release, node resource failure, etc.
S103, when receiving the resource change message, the nfs client connects with a new node.
On the basis of S102, this step aims at the nfs client connecting a new node when receiving the resource change message. That is, after knowing that the main node has failed, the method directly connects the new node and acquires the corresponding nfs service. Instead of performing the node switching operation after finding the tcp connection is in problem in the prior art.
Further, this embodiment may further include:
the nfs client sends a subscription cancellation request to the secondary node so that the secondary node deletes the nfs client from the registration list.
Therefore, in the alternative scheme, the information subscribed by the nfs client through the auxiliary node is mainly deleted, that is, the corresponding subscription operation is cancelled.
Further, this embodiment may further include:
when the auxiliary node receives the registration request, the nfs client is recorded into a registration list, and the main node connected with the nfs client is monitored according to a preset period.
It can be seen that the present alternative scheme mainly explains the operation of the secondary node. In the alternative scheme, when the auxiliary node receives the registration request, the nfs client is recorded into the registration list, and the main node connected with the nfs client is monitored according to a preset period. And when the change of the running state of the main node is monitored, sending a corresponding resource change message to the nfs client.
In summary, in the embodiment, by the determined auxiliary node, after the main node fails, the auxiliary node notifies the nfs client that the failure occurs, instead of discovering the failure through tcp connection, so as to further perform node switching, thereby improving the efficiency of repairing after the failure.
A node failure processing method provided in the present application is further described below by a specific embodiment.
In the embodiment, the witness service between the nfs client and the nfs server is mainly realized. In a distributed system, different nodes provide nfs shared services to the outside through different ip addresses, and based on uniform domain name service, when different nfs clients try to mount the shared services, different nfs clients can be respectively divided into different nodes to provide services, so that load balance of the services is realized.
Each service node in the system maintains available nodes and an ip list in the whole system, and when a single nfs client is connected to one node, a request of GetNodeList is sent to a server, so that all available node addresses in the distributed system are obtained; then the nfs client selects an auxiliary node from other nodes which do not establish connection to establish witness service.
The nfs client needs to send a registration request to the selected auxiliary node, which indicates that the nfs client needs to subscribe to a resource change request related to the current service node, and the server responds to the nfs client with a unique id indicating the validity of the nfs client.
Then, the nfs client sends a notify request to the auxiliary node, where the request carries a resource change type to be received, including ip resources of the service node, shared resources, node failure, and process resources providing services. And when the auxiliary node receives a notify request of the nfs client, adding the nfs client to a subscription list of the corresponding resource.
When the node providing the service has resources or node failure, the auxiliary node can monitor the messages, and then respond the changed resources to the corresponding registered nfs client through notify messages. After receiving the message of resource change, the nfs client will quickly switch the connection to switch the nfs service to other available nodes.
When the nfs client does not need to subscribe to the resource change message of the service node, the nregister message can be sent to the auxiliary node and deleted from the registration list of the auxiliary node; the secondary node will not send notify messages to the nfs client after discovering the change in serving node resources.
Therefore, in the embodiment, through the determined auxiliary node, when the main node fails, the auxiliary node notifies the nfs client that the failure occurs, instead of discovering the failure through tcp connection, so that node switching is further performed, and the efficiency of repairing after the failure is improved.
In the following, the node fault processing apparatus provided in the embodiment of the present application is introduced, and the node fault processing apparatus described below and the node fault processing method described above may be referred to correspondingly.
Referring to fig. 2, fig. 2 is a schematic structural diagram of a node fault handling apparatus according to an embodiment of the present disclosure.
In this embodiment, the apparatus may include:
the available node request module 100 is configured to send an available node request to the nfs server after the nfs client establishes a connection with the nfs server, so that the nfs server returns an available node address list;
an auxiliary node determining module 200, configured to determine an auxiliary node from the available node address list, and send a registration request to the auxiliary node, so that when a master node connected to the nfs client fails, the auxiliary node sends a resource change message to the nfs client;
and a node failover module 300, configured to, when receiving the resource change message, connect the nfs client to a new node.
Optionally, the apparatus may further include:
the resource subscription module is used for sending a resource subscription request to the auxiliary node so that the auxiliary node adds the nfs client to a subscription list of the corresponding node according to the resource subscription request, and when the corresponding node has a resource available condition, a resource change message is sent to the nfs client; and connecting the corresponding nodes according to the resource change message.
Optionally, the apparatus may further include:
and the subscription cancellation module is used for sending a subscription cancellation request to the auxiliary node by the nfs client so that the auxiliary node deletes the nfs client from the registration list.
Optionally, the auxiliary node is further configured to record the nfs client into a registration list when the auxiliary node receives a registration request, and monitor a master node connected to the nfs client according to a preset period.
An embodiment of the present application further provides a server, including:
a memory for storing a computer program;
a processor for implementing the steps of the node failure handling method according to the above embodiments when executing the computer program.
The embodiments of the present application also provide a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the node fault processing method according to the above embodiments are implemented.
The embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
A node failure processing method, a node failure processing apparatus, a server, and a computer-readable storage medium provided by the present application are described in detail above. The principles and embodiments of the present application are explained herein using specific examples, which are provided only to help understand the method and the core idea of the present application. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present application without departing from the principle of the present application, and such improvements and modifications also fall within the scope of the claims of the present application.

Claims (10)

1. A node fault handling method is characterized by comprising the following steps:
after an nfs client is connected with an nfs server, the nfs client sends an available node request to the nfs server, so that the nfs server returns an available node address list;
determining an auxiliary node from the available node address list, and sending a registration request to the auxiliary node, so that when a main node connected with the nfs client fails, the auxiliary node sends a resource change message to the nfs client;
and when the resource change message is received, the nfs client is connected with a new node.
2. The node failover method of claim 1, further comprising:
the nfs client sends a resource subscription request to the auxiliary node, so that the auxiliary node adds the nfs client to a subscription list of a corresponding node according to the resource subscription request, and sends a resource change message to the nfs client when the corresponding node has a resource available condition;
and connecting corresponding nodes according to the resource change message.
3. The node failover method of claim 1, further comprising:
and the nfs client sends a subscription cancellation request to the auxiliary node so that the auxiliary node deletes the nfs client from the registration list.
4. The node failover method of claim 1, further comprising:
and when the auxiliary node receives the registration request, recording the nfs client into a registration list, and monitoring the main node connected with the nfs client according to a preset period.
5. A node failure handling apparatus, comprising:
the system comprises an available node request module, a node address list module and a node address list module, wherein the available node request module is used for sending an available node request to an nfs server after an nfs client is connected with the nfs server so that the nfs server can return the available node address list;
an auxiliary node determining module, configured to determine an auxiliary node from the available node address list, and send a registration request to the auxiliary node, so that when a master node connected to the nfs client fails, the auxiliary node sends a resource change message to the nfs client;
and the node fault switching module is used for connecting the nfs client with a new node when the resource change message is received.
6. The node fault handling apparatus according to claim 5, further comprising:
the resource subscription module is used for sending a resource subscription request to the auxiliary node so that the auxiliary node adds the nfs client to a subscription list of a corresponding node according to the resource subscription request, and when the corresponding node has a resource available condition, a resource change message is sent to the nfs client; and connecting corresponding nodes according to the resource change message.
7. The node fault handling apparatus according to claim 5, further comprising:
and the subscription cancellation module is used for sending a subscription cancellation request to the auxiliary node by the nfs client so that the auxiliary node can delete the nfs client from a registration list.
8. The node fault handling apparatus according to claim 5, wherein the secondary node is further configured to record the nfs client in a registration list when the secondary node receives the registration request, and monitor a primary node to which the nfs client is connected according to a preset period.
9. A server, comprising:
a memory for storing a computer program;
a processor for implementing the steps of the node failure handling method according to any of claims 1 to 4 when executing the computer program.
10. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, which computer program, when being executed by a processor, carries out the steps of the node failure handling method according to any one of claims 1 to 4.
CN202011357395.2A 2020-11-27 2020-11-27 Node fault processing method and related device Withdrawn CN112671554A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113852506A (en) * 2021-09-27 2021-12-28 深信服科技股份有限公司 Fault processing method and device, electronic equipment and storage medium
CN114201117A (en) * 2021-12-22 2022-03-18 苏州浪潮智能科技有限公司 Cache data processing method and device, computer equipment and storage medium
CN114785465A (en) * 2022-04-26 2022-07-22 上海识装信息科技有限公司 Method, server and storage medium for realizing remote multi-activity

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113852506A (en) * 2021-09-27 2021-12-28 深信服科技股份有限公司 Fault processing method and device, electronic equipment and storage medium
CN113852506B (en) * 2021-09-27 2024-04-09 深信服科技股份有限公司 Fault processing method and device, electronic equipment and storage medium
CN114201117A (en) * 2021-12-22 2022-03-18 苏州浪潮智能科技有限公司 Cache data processing method and device, computer equipment and storage medium
CN114201117B (en) * 2021-12-22 2023-09-01 苏州浪潮智能科技有限公司 Processing method and device for cache data, computer equipment and storage medium
CN114785465A (en) * 2022-04-26 2022-07-22 上海识装信息科技有限公司 Method, server and storage medium for realizing remote multi-activity
CN114785465B (en) * 2022-04-26 2024-04-12 上海识装信息科技有限公司 Implementation method, server and storage medium for multiple activities in different places

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Application publication date: 20210416