High-stability redundant FC switch system based on FC protocol

Abstract

The present invention is directed to the field of FC communication technology, and provides a high-stability redundant FC switch system based on the FC protocol, comprising a first FC switch module and a second FC switch module configured to form a redundant architecture design between at least two terminal devices, which are connected via a cascade port. The two FC switch modules are configured with the same domain_ID and routing table. When a single-side link fails, during the information exchange between the first terminal device and the second terminal device, communication is performed via the link on the other side; when a link on the opposite side fails, during the information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switch module and the second FC switch module. In this way, when an FC switch port link fails, as long as the same group of redundant ports do not fail at the same time, reliable message transmission can be achieved, thereby improving the stability and reliability of message transmission.

Description

Technical Field

[0001] The present invention relates to the field of FC communication technology, and in particular to a high-stability redundant FC switch system based on the FC protocol. Background Art

[0002] In the FC switching field, in order to ensure the stability of communication transmission, a redundancy mechanism is used to transmit data, such as Figure 1 The figure shows a traditional FC communication redundancy architecture, using two FC switch modules as an example. FC switch module #1 and FC switch module #2 are redundant. The two switch modules are identically configured. During information exchange, both modules share the same domain_ID and routing table settings. Terminal device #1 and terminal device #2 each have a pair of redundant ports, connected to the two redundant FC switch modules.

[0003] like Figure 1 As shown, under normal circumstances, when terminal device #1 needs to transmit a message to terminal device #2, terminal device #1 sends the message to FC_port1 of FC switch module #1 and FC switch module #2 simultaneously through its own redundant port. After receiving the message from their respective FC_port1, FC switch module #1 and FC switch module #2 respectively route and forward the message to FC_port2, and then send it to the redundant port of terminal device #2 through FC_port2.

[0004] During system operation, if a FC switch module fails, messages can still be transmitted through another redundant FC switch module, ensuring uninterrupted message transmission. The redundant structure design increases the stability of data transmission in the entire system.

[0005] In addition, when a signal path on one side fails, such as the failure of individual path 1, individual path 3, or simultaneous failure of paths 1 and 3 in the figure, the message can still be transmitted through the path corresponding to the other redundant FC switching module, thus ensuring that the message transmission is not interrupted.

[0006] exist Figure 1 In the system shown, if terminals 1 and 4 fail simultaneously, or terminals 2 and 3 fail simultaneously, the communication between terminal device #1 and terminal device #2 will be interrupted.

[0007] Furthermore, to meet the needs of message monitoring, both FC switch module #1 and FC switch module #2 have monitoring ports. However, in actual use, if only one FC switch module is connected to a monitoring device and a line failure occurs on that FC switch module, normal information monitoring will not be possible. For example, if the monitoring port of FC switch module #1 is connected to a monitoring device while the monitoring port of FC switch module #2 is not, and message path line 1 fails, the monitoring port of FC switch module #1 will be unable to monitor the message flow.

[0008] From the above description, we can see that the current redundant system settings can increase the stability of message transmission to a certain extent, but in some specific situations it is still impossible to achieve stable message transmission. Summary of the Invention

[0009] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an optimized design of a high-stability redundant FC switch system based on the FC protocol, and a communication and information processing mechanism between FC switch module #1 and FC switch module #2. When an FC switch port link fails, as long as the failure does not occur simultaneously on the same group of redundant ports, normal message transmission and effective message monitoring can be achieved.

[0010] To achieve the above objectives, a first aspect of the present invention provides a high-stability redundant FC switch system based on the FC protocol, comprising a first FC switch module and a second FC switch module configured to form a redundant architecture between at least two terminal devices, wherein the configurations of the first FC switch module and the second FC switch module remain identical;

[0011] During information exchange between the two terminal devices, the first FC switch module and the second FC switch module are configured with the same domain_ID and routing table, and the first FC switch module and the second FC switch module are connected via a cascade port based on the FC protocol;

[0012] The links connecting the pair of redundant ports of the first terminal device to the first FC switch module and the second FC switch module are respectively recorded as the first link and the second link. The links connecting the first FC switch module and the second FC switch module to the pair of redundant ports of the second terminal device are respectively recorded as the third link and the fourth link. The link connecting the cascade port between the first FC switch module and the second FC switch module is recorded as the fifth link.

[0013] Under normal circumstances, the first terminal device sends information to the first and second FC switch modules of the redundant architecture via the first and second links. After receiving the message, the first FC ports of the first and second FC switch modules perform routing based on the destination port, determine the target FC port, and transmit the message to the second terminal device via the third and fourth links of the first and second FC switch modules, respectively.

[0014] When a single-side link fails, during information exchange between the first terminal device and the second terminal device, communication is performed through the link on the other side;

[0015] Furthermore, when a failure occurs in the opposite link, during information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switch module and the second FC switch module.

[0016] As an optional implementation, when the first link fails, the third link fails, or both the first and third links fail, or when the second link fails, the fourth link fails, or both the second and fourth links fail, during information exchange between the first terminal device and the second terminal device, communication is performed via a link on the other side that has not failed. When the first link and the fourth link fail simultaneously, or when the second link and the third link fail simultaneously, during information exchange between the first terminal device and the second terminal device, communication is performed via a fifth link formed by the cascade port between the first FC switch module and the second FC switch module.

[0017] As an optional implementation, when a message is sent from a pair of redundant ports of the first terminal device to the first FC ports of the first FC switch module and the second FC switch module, the destination FC port is determined by internal routing of the first FC switch module and the second FC switch module:

[0018] If the destination FC port is in the link state, the first FC port of the first FC switch module directly initiates a message transmission request to the destination FC port of the first FC switch module. After the destination FC port of the first FC switch module responds to the request, the first FC port of the first FC switch module starts to transmit the message to the destination FC port of the first FC switch module.

[0019] If the link on the same side as the first FC port of the first FC switch module fails and the destination FC port of the first FC switch module is in an unlinked state, the first FC switch module initiates a message sending request to its cascade port and waits for a response. After the cascade port responds to the request, the first FC port of the first FC switch module sends the message to the cascade port of the second FC switch module through the cascade port of the first FC switch module. The first FC port detects the end-of-frame signal of the message, marks the message sending as complete, and releases the corresponding message buffer in the first FC switch module.

[0020] As an optional implementation, when the first FC port of the first FC switch module receives a data frame from the first terminal device, the frame type is determined according to the destination FCID of the data frame and the data frame is buffered, wherein:

[0021] If the frame type is a unicast frame, the routing table is directly queried to determine the destination FC port of the route; if the frame type is a multicast or broadcast frame, the routing table is queried to determine all destination FC ports;

[0022] Furthermore, for unicast frames, the link status of the destination FC port is directly determined. For multicast or broadcast frames, if all destination FC ports are linked, the frame is considered to be in the linked state; if at least one of the destination ports is not linked, the frame is considered to be in the unlinked state.

[0023] 6. The high-stability redundant FC switch system based on the FC protocol according to claim 4, wherein in the second FC switch module, when the cascade port of the second FC switch module receives a data frame sent from the first FC switch module, the source FCID of the received data frame is queried, the source port is determined, and the data frame is cached, wherein:

[0024] If the source port of the second FC switch module is in normal working state, that is, the source port of the message is in the link state, the cascade port of the second FC switch module will directly discard the received data frame and release the buffer;

[0025] If the source port of the second FC switch module is in a faulty device, that is, the source port of the message is in an unlinked state, the cascade port of the second FC switch module will query the routing table to determine the target FC port of the second FC switch module, initiate a message sending request to the target FC port of the second FC switch module, and wait for a response. After receiving the response message from the target FC port of the second FC switch module, the cascade port of the second FC switch module will transmit the data frame to the target FC port of the second FC switch module, and upon detecting the frame tail signal of the message, mark the message sending as completed and release the corresponding message buffer in the second FC switch module.

[0026] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below, as long as such concepts are not mutually inconsistent, can be considered part of the inventive subject matter of this disclosure. In addition, all combinations of the claimed subject matter are considered part of the inventive subject matter of this disclosure.

[0027] The foregoing and other aspects, embodiments, and features of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as features and / or beneficial effects of the exemplary embodiments, will become apparent from the following description or through practice of specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings.

[0029] Figure 1 This is a schematic diagram of the redundant architecture of traditional FC communication in the prior art.

[0030] Figure 2 FIG. 4 is a schematic diagram of a redundant architecture of FC communication according to an exemplary embodiment of the present invention.

[0031] Figure 3 The diagram is a flow chart of message processing after a first FC switch module receives a data frame in a high-stability redundant FC switch system according to an exemplary embodiment of the present invention.

[0032] Figure 4 The diagram is a flow chart of message processing after a second FC switch module receives a data frame in a high-stability redundant FC switch system according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to better understand the technical content of the present invention, specific embodiments are given below in conjunction with the accompanying drawings.

[0034] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed herein are not limited to any embodiment. In addition, some aspects of the present disclosure may be used alone or in any appropriate combination with other aspects disclosed herein.

[0035] Combine Figure 2 As shown, a high-stability redundant FC switch system based on the FC protocol according to an embodiment of the present invention includes a first FC switching module and a second FC switching module that form a redundant architecture design between at least two terminal devices, and the configurations of the first FC switching module and the second FC switching module remain the same.

[0036] During information exchange between two terminal devices, the first FC switch module and the second FC switch module are configured with the same domain_ID and routing table, and the first FC switch module and the second FC switch module are connected via a cascade port based on the FC protocol.

[0037] exist Figure 2 In the example shown, each FC switch module (#1, #2) can be configured with multiple FC ports (FC_port). FC switch module #1 and FC switch module #2 are redundant FC switch modules with identical configurations. During information exchange, the two switch modules have the same domain_ID and routing table settings. The two redundant FC switch modules are connected via multiple cascade ports.

[0038] As a preferred example, each FC switch module (#1, #2) may be designed with multiple monitoring ports.

[0039] The links connecting the pair of redundant ports of the first terminal device to the first FC switch module and the second FC switch module are respectively recorded as the first link and the second link. The links connecting the first FC switch module and the second FC switch module to the pair of redundant ports of the second terminal device are respectively recorded as the third link and the fourth link. The link connecting the cascade port between the first FC switch module and the second FC switch module is recorded as the fifth link.

[0040] like Figure 2 The figure shows the communication between terminal device #1 and terminal device 2. Terminal device #1's pair of redundant ports connects to FC_port 1 on FC switch modules #1 and #2, with the connection paths labeled link 1 and link 2. Terminal device #2's pair of redundant ports connects to FC_port 2 on FC switch modules #1 and #2, with the connection paths labeled link 3 and link 4. FC switch modules #1 and #2 are connected via a cascade port, labeled link 5.

[0041] Under normal circumstances, the first terminal device sends information to the first FC switch module and the second FC switch module of the redundant architecture through the first link and the second link. After receiving the message, the first FC ports of the first FC switch module and the second FC switch module perform routing based on the destination port, determine the target FC port, and transmit the message to the second terminal device via the third link and the fourth link of the first FC switch module and the second FC switch module, respectively.

[0042] When a single-side link fails, communication is performed through the link on the other side during information exchange between the first terminal device and the second terminal device.

[0043] For example, when the first link fails, the third link fails, or the first link and the third link fail at the same time, or when the second link, the fourth link, or the second link and the fourth link fail at the same time, during the information exchange between the first terminal device and the second terminal device, communication is performed through the link on the other side that has not failed.

[0044] When a failure occurs in the opposite link, during information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switch module and the second FC switch module.

[0045] For example, when the first link and the fourth link fail simultaneously, or the second link and the third link fail simultaneously, during information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switching module and the second FC switching module.

[0046] Combine Figure 2 As shown, under normal circumstances, terminal device #1 sends information to redundant FC switch module #1 and FC switch module #2 through links 1 and 2. After receiving the message, FC_port1 of FC switch module #1 and FC switch module #2 routes the message to FC_port2 based on the destination port. FC switch module #1 and FC switch module #2 then transmit the message to terminal device #2 through links 3 and 4 through FC_port2.

[0047] When a single link fails, such as link 1 or 3 fails, or link 1 and 3 fail simultaneously, or link 2 or 4 fails, or link 2 and 4 fail simultaneously, messages can still be communicated through the link on the other side.

[0048] When the link on the opposite side fails, for example, link 1, link 4, or both fail, or link 2, link 3, or both fail, the message can be communicated through the fifth link (i.e., link 5) formed by the cascade port between the redundant FC switch module #1 and FC switch module #2.

[0049] A plurality of cascade ports are configured between the first FC switch module and the second FC switch module to implement a cascade connection between the two, thereby ensuring reliable data transmission between the two terminal devices even when some of the cascade ports fail.

[0050] As an optional implementation, when a pair of redundant ports of the first terminal device sends data to the first FC ports of the first FC switch module and the second FC switch module, the destination FC port is determined by internal routing of the first FC switch module and the second FC switch module:

[0051] If the destination FC port is in the link state, the first FC port of the first FC switch module directly initiates a message transmission request to the destination FC port of the first FC switch module. After the destination FC port of the first FC switch module responds to the request, the first FC port of the first FC switch module starts to transmit the message to the destination FC port of the first FC switch module.

[0052] If the link on the same side as the first FC port of the first FC switch module fails and the destination FC port of the first FC switch module is in an unlinked state, the first FC switch module initiates a message sending request to its cascade port and waits for a response. After the cascade port responds to the request, the first FC port of the first FC switch module sends the message to the cascade port of the second FC switch module through the cascade port of the first FC switch module. The first FC port detects the end-of-frame signal of the message, marks the message sending as complete, and releases the corresponding message buffer in the first FC switch module.

[0053] As an optional implementation, when the first FC port of the first FC switch module receives a data frame from the first terminal device, the frame type is determined according to the destination FCID of the data frame and the data frame is buffered, wherein:

[0054] If the frame type is a unicast frame, the routing table is directly queried to determine the destination FC port of the route; if the frame type is a multicast or broadcast frame, the routing table is queried to determine all destination FC ports;

[0055] Furthermore, for unicast frames, the link status of the destination FC port is directly determined. For multicast or broadcast frames, if all destination FC ports are linked, the frame is considered to be in the linked state; if at least one of the destination ports is not linked, the frame is considered to be in the unlinked state.

[0056] As an optional implementation, in the second FC switch module, when the cascade port of the second FC switch module receives a data frame sent from the first FC switch module, the source FCID of the received data frame is queried, the source port is determined, and the data frame is cached, wherein:

[0057] If the source port of the second FC switch module is in normal working state, that is, the source port of the message is in the link state, the cascade port of the second FC switch module will directly discard the received data frame and release the buffer;

[0058] If the source port of the second FC switch module is in a faulty device, that is, the source port of the message is in an unlinked state, the cascade port of the second FC switch module will query the routing table to determine the target FC port of the second FC switch module, initiate a message sending request to the target FC port of the second FC switch module, and wait for a response. After receiving the response message from the target FC port of the second FC switch module, the cascade port of the second FC switch module will transmit the data frame to the target FC port of the second FC switch module, and upon detecting the frame tail signal of the message, mark the message sending as completed and release the corresponding message buffer in the second FC switch module.

[0059] {Example 1}

[0060] Combine Figure 2 、 3 As shown in FIG. 4 , we will combine the redundant architecture design composed of two FC switching modules (FC switching module #1 and FC switching module #2) to specifically explain the message processing process between two terminal devices (terminal device #1 and terminal device #2) according to the method of the present invention.

[0061] Combine Figure 2 As for the aforementioned embodiment, under normal circumstances, terminal device #1 sends information to redundant FC switch module #1 and FC switch module #2 via links 1 and 2. After receiving the message, FC_port 1 of FC switch module #1 and FC switch module #2 routes the message to FC_port 2 according to the destination port. FC switch module #1 and FC switch module #2 then transmit the message to terminal device #2 via links 3 and 4 via FC_port 2.

[0062] When a single link fails, such as links 1 and 3 failing at the same time, or links 2 and 4 failing at the same time, messages can still be communicated through the link on the other side.

[0063] When link 1 and link 4, or link 2 and link 3, fail simultaneously, reliable message transmission is achieved through the cascade port between FC switch module #1 and FC switch module #2.

[0064] The following describes the message processing process using the example of simultaneous failure of link 2 and link 3.

[0065] Combine Figure 3 In the process shown, in FC switch module #1, when FC switch module #1 receives a data frame sent by terminal device #1, it processes it according to the following process.

[0066] 1. FC_port 1 of FC switch module #1 receives a data frame from terminal device #1.

[0067] 2. Determine the frame type based on the destination FCID of the data frame: If the frame type is a unicast frame, directly query the routing table to determine the destination port of the route. Figure 2 In this example, FC_port2 is used as the destination port. If the frame type is a multicast or broadcast frame, the routing table is queried to determine all destination ports (assuming that the destination port includes FC_port2).

[0068] 3. Cache the received frame data, which can be implemented according to the existing FC communication cache method, such as implementing data cache in the FPGA;

[0069] 4. Determine the link status of the destination port. If it is unicast, directly determine the link status of the destination port FC_port2;

[0070] If it is a multicast or broadcast, if all destination ports are linked, it is considered linked; if at least one of the destination ports is not linked, it is considered unlinked.

[0071] 5. FC_port 2 of FC switch module #1 is in the disconnected state due to a link 3 failure. FC_port 1 of FC switch module #1 then directly initiates a message send request to the cascade port of FC switch module #1 and waits for a response.

[0072] 6. The cascade port on FC switch module #1 responds to the request, and FC_port1 on FC switch module #1 sends the message to the cascade port on FC switch module #2 through the cascade port on FC switch module #1.

[0073] 7. FC_port 1 of FC switch module #1 detects the end-of-frame signal and marks the message as sent successfully, thereby releasing the corresponding buffer in FC switch module #1.

[0074] Combine Figure 3In the aforementioned process, if FC_port2 of FC switch module #1 is in the linked state when the message arrives at FC_port1 of FC switch module #1, FC_port1 of FC switch module #1 will directly initiate a message transmission request to FC_port2. After FC_port2 responds to the request, FC_port1 of FC switch module #1 will begin transmitting the message to FC_port2. If link 3 fails at this time, meaning that FC_port2 of FC switch module #1 is unlinked, the process returns to step 5. After determining that FC_port2 of FC switch module #1 is unlinked, the message is resent to the cascade port of FC switch module #1.

[0075] As can be seen from the above message processing flow, when a failure occurs on the destination port, regardless of whether a problem occurs during message arrival or during message transmission, the message receiving port can respond promptly and send the message through the cascade ports between the redundant FC switch modules for processing. This ensures that no frame is lost during transmission due to unlinked destination ports on the local FC switch modules, thus achieving reliable data transmission.

[0076] Combine Figure 2 、 4 As shown in the figure, when the cascade port of FC switch module #2 receives a data frame sent by FC switch module #1, the specific message processing flow is as follows:

[0077] 1. The cascade port on FC switch module #2 receives a data frame from the cascade port on FC switch module #1.

[0078] 2. Query the source FCID of the received data frame and determine that the source port is FC_port1;

[0079] 3. Cache this frame information;

[0080] 4. Check the link status of source port FC_port1 on FC switch module #2. Due to a link 2 failure, FC_port1 on FC switch module #2 is in the unlinked state.

[0081] 5. Query the destination FCID of the data frame and determine that the destination port of this frame is FC_port2;

[0082] 6. Initiate a message send request to FC_port 2 of FC switch module #2 and wait for a response;

[0083] 7. FC_port 2 of FC switch module #2 is in normal link status. The cascade port of FC switch module #2 receives the response and starts message transmission.

[0084] 8. Detect the frame end signal, determine that the frame transmission is completed, and release the cache.

[0085] Combine Figure 4 In the aforementioned message processing process, if port FC_port1 of FC switch module #2 is in normal working state at this time, that is, the source port FC_port1 of the message is in the link state, after receiving the message, the cascade port of FC switch module #2 determines that the source port is in the normal link state, directly discards the frame content, and releases the buffer at the same time.

[0086] To improve system stability, multiple cascade ports can be designed between FC switch module #1 and FC switch module #2 to ensure reliable information transmission through the above solution even if individual cascade ports fail.

[0087] Through the system design and message processing described above, even when a FC switch port link fails, messages can still be transmitted normally, as long as the failures do not occur simultaneously on the same set of redundant ports. This allows the monitoring device connected to the monitoring port to still monitor message transmission across all ports in the event of a link failure. Therefore, compared to traditional redundancy solutions, the present invention's optimized redundancy design for FC communication significantly improves the stability and reliability of message transmission.

[0088] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A high-stability redundant FC switch system based on the FC protocol, characterized in that: The first FC switch module and the second FC switch module are configured to form a redundant architecture between at least two terminal devices, wherein the configurations of the first FC switch module and the second FC switch module remain identical; During information exchange between the two terminal devices, the first FC switch module and the second FC switch module are configured with the same domain_ID and routing table, and the first FC switch module and the second FC switch module are connected via a cascade port based on the FC protocol; The links connecting the pair of redundant ports of the first terminal device to the first FC switch module and the second FC switch module are respectively recorded as the first link and the second link. The links connecting the first FC switch module and the second FC switch module to the pair of redundant ports of the second terminal device are respectively recorded as the third link and the fourth link. The link connecting the cascade port between the first FC switch module and the second FC switch module is recorded as the fifth link. Under normal circumstances, the first terminal device sends information to the first and second FC switch modules of the redundant architecture via the first and second links. After receiving the message, the first FC ports of the first and second FC switch modules perform routing based on the destination port, determine the target FC port, and transmit the message to the second terminal device via the third and fourth links of the first and second FC switch modules, respectively. When a single-side link fails, during information exchange between the first terminal device and the second terminal device, communication is performed through the link on the other side; Furthermore, when a failure occurs in the opposite link, during information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switch module and the second FC switch module.

2. The high-stability redundant FC switch system based on the FC protocol according to claim 1, characterized in that: When the first link fails, the third link fails, and the first link and the third link fail at the same time, or when the second link, the fourth link, and the second link and the fourth link fail at the same time, during the information exchange between the first terminal device and the second terminal device, communication is performed through the link on the other side that has not failed.

3. The high-stability redundant FC switch system based on the FC protocol according to claim 1, characterized in that: When the first link and the fourth link fail simultaneously, or when the second link and the third link fail simultaneously, during information exchange between the first terminal device and the second terminal device, communication is performed via the fifth link formed by the cascade port between the first FC switching module and the second FC switching module.

4. The high-stability redundant FC switch system based on the FC protocol according to claim 1, characterized in that: When a message is sent from a pair of redundant ports of the first terminal device to the first FC port of the first FC switch module and the second FC switch module, the destination FC port is determined by the internal routing of the first FC switch module and the second FC switch module: If the destination FC port is in the link state, the first FC port of the first FC switch module directly initiates a message transmission request to the destination FC port of the first FC switch module. After the destination FC port of the first FC switch module responds to the request, the first FC port of the first FC switch module starts to transmit the message to the destination FC port of the first FC switch module. If the link on the same side as the first FC port of the first FC switch module fails and the destination FC port of the first FC switch module is in an unlinked state, the first FC switch module initiates a message sending request to its cascade port and waits for a response. After the cascade port responds to the request, the first FC port of the first FC switch module sends the message to the cascade port of the second FC switch module through the cascade port of the first FC switch module. The first FC port detects the end-of-frame signal of the message, marks the message sending as complete, and releases the corresponding message buffer in the first FC switch module.

5. The high-stability redundant FC switch system based on the FC protocol according to claim 4, characterized in that: When the first FC port of the first FC switch module receives a data frame from the first terminal device, the frame type is determined according to the destination FCID of the data frame and the data frame is buffered. If the frame type is a unicast frame, the routing table is directly queried to determine the destination FC port of the route; if the frame type is a multicast or broadcast frame, the routing table is queried to determine all destination FC ports; Furthermore, for unicast frames, the link status of the destination FC port is directly determined. For multicast or broadcast frames, if all destination FC ports are linked, the frame is considered to be in the linked state; if at least one of the destination ports is not linked, the frame is considered to be in the unlinked state.

6. The high-stability redundant FC switch system based on the FC protocol according to claim 4, characterized in that: In the second FC switch module, when the cascade port of the second FC switch module receives a data frame sent from the first FC switch module, the source FCID of the received data frame is queried, the source port is determined, and the data frame is cached, wherein: If the source port of the second FC switch module is in normal working state, that is, the source port of the message is in the link state, the cascade port of the second FC switch module will directly discard the received data frame and release the buffer; If the source port of the second FC switch module is in a faulty device, that is, the source port of the message is in an unlinked state, the cascade port of the second FC switch module will query the routing table to determine the target FC port of the second FC switch module, initiate a message sending request to the target FC port of the second FC switch module, and wait for a response. After receiving the response message from the target FC port of the second FC switch module, the cascade port of the second FC switch module will transmit the data frame to the target FC port of the second FC switch module, and upon detecting the frame tail signal of the message, mark the message sending as completed and release the corresponding message buffer in the second FC switch module.

7. The high-stability redundant FC switch system based on the FC protocol according to any one of claims 1 to 6, characterized in that: The first FC switch module and the second FC switch module are both configured with multiple monitoring ports.

8. The high-stability redundant FC switch system based on the FC protocol according to any one of claims 1 to 6, characterized in that: A plurality of cascade ports are configured between the first FC switch module and the second FC switch module to implement a cascade connection between the two, thereby ensuring that data transmission between the two terminal devices can still be achieved when some of the cascade ports fail.

Images