JP4675664B2 - Processor load balancing system and processor load balancing method - Google Patents

Description

  The present invention relates to a processor load distribution system and a processor load distribution method in a computer system that accesses a plurality of targets from a plurality of initiators via a plurality of ports. Specifically, the present invention relates to an iSCSI storage device equipped with a plurality of ports. The present invention relates to a processor load distribution system and a processor load distribution method capable of distributing loads via ports when accessing from a plurality of hosts.

  In recent years, as an external storage device of a computer system, a storage system incorporating a large number of magnetic disk devices is known. This storage system incorporates a large number of magnetic disk devices and employs a technology for managing as a redundant magnetic disk device by combining a plurality of magnetic disk devices called RAID. For example, the storage system is connected to a network system and is connected to a large number of host computers. (Hereinafter referred to as a host) is used as a data storage area.

  This storage system has a plurality of ports for external connection, and is configured to access an arbitrary magnetic disk device from an arbitrary host via an arbitrary port via a switch.

  On the other hand, a technique called “iSCSI (ice caddy)” has recently been proposed as a technique for connecting the storage systems to the network. This iSCSI wraps a SCSI command and data in a TCP / IP packet transmission frame (hides the SCSI command and the like from the outside), connects the storage system directly to the network, and transfers the SCSI command between the storage system and the host to the IP. This is a standard for sending and receiving over a network.

On the other hand, for example, in a computer system in which a plurality of clients access a plurality of servers via a network, in order to prevent the load from being concentrated on a specific server, the load in the connection state is monitored, and according to the monitored load state As a document describing a technique for distributing a load, for example, the following patent publications can be cited.
JP 10-31365 A JP-A-11-187340

  In a system in which the storage system described above is connected to a plurality of hosts via a network via iSCSI, an iSNS server that manages connection information of the iSCSI system is set in advance in response to an inquiry from the host (also referred to as an initiator). A list of magnetic disk devices (also called targets) is returned, and the host selects an arbitrary magnetic disk device (target) port from the list to send and receive data. There is a problem that the host is connected and the processor load of the port increases, which may reduce the data transmission / reception efficiency in the network.

  On the other hand, the load distribution method in the general computer system described above has a dedicated device for monitoring the load in the data transfer path, and this dedicated monitoring device controls the load distribution. However, there is a problem that there is a possibility that the load is concentrated on the specific port.

  An object of the present invention is to eliminate the above-mentioned problems caused by the prior art, and a processor capable of preventing load concentration on a specific port in a network-connected storage system using iSCSI technology and performing load distribution. A load distribution system and a processor load distribution method are provided.

In order to achieve the above object, the invention according to claim 1 includes a configuration information table including a plurality of ports and a plurality of target images via the ports, and including connection information indicating a dynamic connection state with the connected initiator. A registration information table storing registration connection information representing a physical connection state between the iSCSI server, the plurality of initiators connected to the iSCSI device via the port, and the port of the iSCSI device and the target image; a processor load balancing system in a computer system comprising an iSNS server, wherein an initiator refers to a registration information table of the iSNS server and connects to a target image of an iSCS device;
When the processor that controls the port refers to the connection information in the configuration information table and detects a load of a predetermined threshold or more on the port, the target image connected to the specific port from the registered connection information in the registration information table The registration information is deleted, the connection between the port to which the target image is connected and the initiator is disconnected, and the disconnected initiator refers to the registration information table and switches the path to the target image to reconnect. Such control is the first feature.

The invention according to claim 2 includes an iSCSI system including a configuration information table including a plurality of ports and a plurality of target images via the ports and including connection information indicating a dynamic connection state with the connected initiator, a plurality of initiators connected to the iSCSI device via the port, and a registration information table iSNS server storing registered connection information indicating a physical connection state between the port of the iSCSI device and the target image. A processor load distribution method in a computer system for referring to a registration information table of the iSNS server and connecting to a target image of an iSCSI device,
When the processor that controls the port refers to the connection information in the configuration information table and the connection to the specific port is greater than or equal to a predetermined threshold, the processor is connected to the specific port from the registered connection information in the registration information table. Deleting the registration information with the target image, disconnecting the connection between the port to which the target image is connected and the initiator, and connecting the target image with the disconnected initiator referring to the registration information table And performing the process .

  The processor load distribution system and the processor load distribution method according to the present invention detect an overload port, and when an overload port is detected, a target connected to the specific port from the registered connection information in the registration information table. Deletes the registered connection information with the image, disconnects the connection between the port to which the target image is connected and the initiator, and controls the disconnected initiator to connect to the target image with reference to the registration information table By doing so, it is possible to distribute the overload to the processor of the port.

  Hereinafter, a processor load distribution system and a processor load distribution method according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram for explaining the overall configuration of a processor load balancing system to which a processor load balancing method according to the present invention is applied, FIG. 2 is a diagram showing a configuration information table of iSCSI storage according to the present embodiment, and FIG. 4 shows a registration information table of the iSNS server according to the present embodiment, FIG. 4 is a flow chart at the time of port switching according to the present embodiment, FIG. 5 is a flow chart of the iSNS server operation at the time of the switching according to the present embodiment, and FIG. FIG. 7 is a sequence diagram at the time of switching, and FIGS. 8 to 13 are operation explanatory diagrams of the processor load distribution system according to the present embodiment.

  As shown in FIG. 1, the processor load distribution system according to the present embodiment is connected to initiators 10a to 10c corresponding to a plurality of hosts, and the initiators 10a to 10c via a switch 20, and manages information during the connection. The iSCSI storage system 40 includes an iSCSI storage system 40 and an iSNS server 30. The iSCSI storage system 40 includes a plurality of target images 43a to 43c corresponding to a magnetic disk device, ports 41a to 41b connected to the switch 20, and the port 41a. And the processor 42b provided in the front port 41b, and the processor 42a and the processor 42b are individually connected to the target images 43a to 43c.

The initiators 10a to 10c refer to devices that issue commands to target target images 43a to 43c. For example, the initiators 10a to 10c indicate host computers. The iSNS server 30 includes ports 41a to 41b in the iSCSI storage system 40. Corresponding logically connected target images 43a to 43c having a registration information table for registering in advance as registration connection information, and referring to the registration information table for inquiries from the initiators 10a to 10c. A function for returning a connectable port as a response, and a function for storing the connection information in a configuration information table.

  For example, as shown in FIG. 2, the registration information includes [port information] that is the IP address of the ports 41a to 41b of the iSCSI storage system 40, [target information] that is the iSCSI name of the target images 43a to 43c, and which initiator. An iSCSI storage configuration information table including [initiator information during login] for managing which target image is logged in, and an iSNS storing an IP address corresponding to the target image (iSCSI name) as shown in FIG. It consists of a server registration information table. The iSCSI storage configuration information table is managed by the iSCSI storage system 40 (iSCSI device), and the iSNS server registration information is managed by the iSNS server 30 and is included in each. The iSNS server 30 updates the iSNS server registration information in accordance with a request from the iSCSI storage system 40.

  Now, in the processor load distribution system according to the present embodiment configured as described above, for example, as shown in FIG. 8, the initiators 10a to 10c are connected to the three target images 43a to 43c via the switch 20 and the port 41a. In the above-described iSCSI storage configuration information table, as indicated by reference numeral 501, it is registered that all the initiators 10a to 10c are connected via the port 41a in [Initiator information during login].

  In this state, as shown in FIG. 4, the processor load distribution system determines whether or not the port 41a is overloaded (step 101). If it is determined that the port 41a is overloaded, the iSCSI storage configuration information table 105 is determined. , A process for searching for connected initiators (step 102) is executed, and then a switching priority order of connected initiators (priority order for selecting an initiator with little trouble even if switching is performed) is determined ( Step 103), and when the target image having a higher priority is determined to be the initiator 10a, a process of searching for the target image to which the initiator 10a is logged in (step 104) is executed. Based on this search, the system determines whether or not the target image 43a is a target connected to a plurality of ports (step 105), and then determines whether or not the switching destination port is overloaded. It is determined whether the load of the port 41b is equal to or less than a threshold value (for example, 2) (step 106). This load monitoring is performed by the processor that controls the port.

  As a result of this determination, if the load on the port 41b is equal to or less than the threshold, the system sends a registration information deletion request (the uppermost item [1] of the table 502 in FIG. 9: target image 43a [eu.0001] to the iSNS server 30. ] (Setting deletion request via the IP address [102.168.100] of the port) (step 107). Upon receiving this registration information deletion request, the iSNS server 30 determines whether or not there is a registration information deletion request (step 205) as indicated by reference symbol A in FIG. 1]) (“[3] Information deletion” in FIG. 9) is executed.

  Next, the processor load distribution system returns to FIG. 4, and the target image 43a issues a logout to the initiator 10a (see step 108, “[4] logout issue” in FIG. 10). Upon receiving this logout, the initiator 10a determines whether or not a logout has been received (step 301) and disconnects the connection to the specified target image (step 302, “[ 5] Connection disconnection processing ”), the target information acquisition request (step 303) is made to the iSNS server 30, and the iSNS server 30 that has received this acquisition request acquires the information as indicated by reference numeral D in FIG. After determining whether there is a request (step 201), a target information transmission process (step 202) is executed.

  The initiator 10a that has received this target information transmission processing executes target information acquisition processing 304 and target login processing ("[7] information acquisition" in FIG. 11) as shown by symbol E in FIG. Since the item [1] is deleted when the 10a refers to the iSNS server registration information table 502, the target is determined by referring to the next item [2], that is, the registration information via the port 41b (FIG. 12). [[8] Login destination target determination] and reconnects to the target image 43a via the port 41b (step 305, "[9] login process" in FIG. 12).

  In this way, that is, the processor load distribution system according to the present embodiment detects an overload port, and when an overload port is detected, information that registers the relationship between the initiator and the port connected to the overload port. In addition to deleting a part of the table 502, the initiator logs on again when the target image side logs off the initiator, and the information table 502 referred to at the time of logging on again is in the overload state. Since the registration information (item [1] indicating the relationship between the initiator and the port) has been deleted, other registration information to which the initiator 10a is connected to the target image 43a (eui.0001) from the registration information, Specifically, log on by selecting item [2] in registration information table 502 of FIG. By Ukoto, it is possible to distribute the overload of the port processor 42a.

  On the other hand, returning to FIG. 4, if it is determined in step 105 or 106 that the target image 43 a is not connected to a plurality of ports or the load is equal to or lower than the threshold value, the system determines other initiators according to the priority order determined in step 103. On the other hand, an initiator switching process (step 109) to be processed is performed in order to repeatedly execute steps 101 to 108.

  Further, when it is determined in step 101 that the port 41a is not in an overload state, the system determines whether or not the load of the port 41a is equal to or less than a threshold value (step 110). It is determined whether or not there is a target image whose registration has been deleted by 107 or the like (step 111). The information registration request (step 112) of the item [1]) of the information table 502 is made, and the iSNS server 30 determines whether or not there is an information registration request as shown by reference C in FIG. 5 (step 203). After performing the target information registration process (step 204, “[10] Information registration request” in FIG. 13). It can thereby return port registration information is not overloaded. The above-described series of operations by the processor load distribution system according to the present embodiment is performed as shown in FIG. In the state, the overload state is detected, the initiator that performs the port switching is determined according to the priority determination, and the target 43a itself makes a request to delete the registration information of the connection, and the iSNS server 30 responds accordingly. After the corresponding registration information is deleted, the connection of the target image 43a through the port 41a is disconnected, and when the initiator 10a performs the connection again, the connection through the port 41b is established, so that the port is overloaded. It can be avoided.

  As described above, according to the present embodiment, the connection state from the initiators 10a to 10c via the ports 41a and 41b of the iSCSI storage system 40 is monitored, and the login via a certain port is greater than or less than a predetermined value. In addition, by dynamically rewriting the registration information table 502 of the iSNS server 30, an overload to a specific port can be automatically distributed.

  In the above-described embodiment, the processor load distribution system and the processor load distribution method of the present invention have been described with an example in which a plurality of magnetic disk devices are used as target images, but the initiator and target image are limited to a host computer or a magnetic disk device. However, the present invention can be applied to control of a wide variety of peripheral devices capable of iSCSI connection.

The figure for demonstrating the whole structure of the processor load distribution system to which the processor load distribution method by this invention is applied. The figure which shows the structure information table of the iSCSI storage by this embodiment. The figure which shows the registration information table of the iSNS server by this embodiment. The flowchart figure at the time of port switching by this embodiment. The iSNS server operation | movement flowchart figure at the time of the switching by this embodiment. The initiator operation | movement flowchart figure at the time of logout reception by this embodiment. The initiator operation | movement sequence diagram at the time of the switching. Operation | movement explanatory drawing of the processor load distribution system by this embodiment. Operation | movement explanatory drawing of the processor load distribution system by this embodiment. Operation | movement explanatory drawing of the processor load distribution system by this embodiment. Operation | movement explanatory drawing of the processor load distribution system by this embodiment. Operation | movement explanatory drawing of the processor load distribution system by this embodiment. Operation | movement explanatory drawing of the processor load distribution system by this embodiment.

10a to 10c: initiator, 43a to 43c: target image, 41a to 41b: port, 20: switch, 30: iSNS server, 40: storage system, 42a: processor, 42b: processor, 502: server registration information table, 502: Registration information table.

Claims (2)

An iSCSI device including a plurality of ports and a plurality of target images via the ports, and including a configuration information table including connection information indicating a dynamic connection state with the connected initiator, and the ports to the iSCSI device. And an iSNS server including a registration information table storing registration connection information representing a physical connection state between a port and a target image of the iSCSI server, and the initiator is a registration information table of the iSNS server. A processor load balancing system in a computer system connected to a target image of an iSCSI device with reference to
When the processor that controls the port refers to the connection information in the configuration information table and detects a load of a predetermined threshold or more on the port, the target image connected to the specific port from the registered connection information in the registration information table The registration information is deleted, the connection between the port to which the target image is connected and the initiator is disconnected, and the disconnected initiator refers to the registration information table and switches the path to the target image to reconnect. The processor load distribution system characterized by controlling as follows. An iSCSI device including a plurality of ports and a plurality of target images via the ports, and including a configuration information table including connection information indicating a dynamic connection state with the connected initiator, and the ports to the iSCSI device. a plurality of initiators connected through the a registration information table iSNS servers that the registration connection information indicating a physical connection state stored in the port and the target image iSCS device, registration initiator of the iSNS server information A processor load balancing method in a computer system for referring to a table and connecting to a target image of an iSCSI device, comprising:
When the processor that controls the port refers to the connection information in the configuration information table and the connection to the specific port is greater than or equal to a predetermined threshold, the processor is connected to the specific port from the registered connection information in the registration information table. Deleting the registration information with the target image, disconnecting the connection between the port to which the target image is connected and the initiator, and connecting the target image with the disconnected initiator referring to the registration information table And a step of executing the processor load distribution method.

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