JP2017111761A - Container storage device, container creation method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly perform control of a resource for every user, in a sharing hosting service in which a server resource is shared among users.SOLUTION: A container storage device for storing a container which is a virtual environment in which a process of a specific user is operated in a separated state from a process of other users, comprises: container management means for, when a container creation instruction of the specific user is received, using model data which is used in common in container creation of each user, creating a container of the specific user. The container management means connects an external area which is outside of the container to a data area which is recognized by the specific user on the container, and allows the data to be stored in the external area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a service providing method in a shared hosting service.

  In recent years, virtual server type hosting services that occupy CPU / memory / disk, such as VPS (Virtual Private Server) and cloud, are spreading. However, in the virtual server type hosting service, a user needs to manage and operate the server for each individual server. On the other hand, by sharing server resources with other users, a shared hosting service that is low-cost and does not require time and effort for server management is widely used mainly by small and medium enterprise users.

  In the conventional method for providing a shared hosting service, a single process is shared by a large number of accommodated users in one housing. Specifically, a shared daemon process is prepared, user users are distributed according to user-specific information such as a domain, and housing resources are shared among accommodated users.

JP 2014-235644

  However, in the method of sharing a process between users as described above, for example, when some accommodated users occupy a large amount of resources, there is a case that other users cannot use the service. . There is also a problem that a common resource setting must be used among all users using the process.

  That is, the conventional technology has a problem in that it is not possible to appropriately control resources for each user in a shared hosting service in which server resources are shared among users.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a technology that enables appropriate control of resources for each user in a shared hosting service in which server resources are shared among users. And

According to an embodiment of the present invention, a container accommodation apparatus that accommodates a container that is a virtual environment in which a process of a specific user is operated separately from other users' processes,
A container management means for creating a container for the specific user by using model data commonly used in creating a container for each user when receiving the container creation instruction for the specific user;
The container management means connects an external area outside the container to a data area recognized by the specific user in the container so that data is stored in the external area. A container storage device is provided.

In addition, according to the embodiment of the present invention, there is provided a container creation method executed by a container accommodation device that accommodates a container that is a virtual environment for operating a specific user process separately from other user processes. And
A container creation step of creating a container for the specific user by using model data commonly used in creating a container for each user when the container creation instruction for the specific user is received;
In the container creation step, the container receiving device connects an external area outside the container to a data area recognized by the specific user in the container, so that data is stored in the external area. A container creation method characterized by the above is provided.

  According to the embodiment of the present invention, it is possible to provide a technique that enables appropriate control of resources for each user in a shared hosting service in which server resources are shared among users.

1 is an overall configuration diagram of a system in an embodiment of the present invention. It is a figure which shows the structural example after the container is produced | generated in the container accommodating apparatus. It is a figure which shows the structure of the container accommodating apparatus 100 more concretely. It is a figure which shows the outline | summary of container creation. It is a figure which shows the example of the content of a template. It is a flowchart which shows the process example at the time of container creation. It is a figure which shows the outline | summary of an update process. It is a flowchart which shows the process example at the time of an update. It is a figure which shows the example of the delivery process of a user area | region template. It is a figure for demonstrating the example which uses properly the storage of user data. It is a figure for demonstrating cooperation with an external service.

  Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below is only an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

(Outline of the embodiment)
In this embodiment, a container template including a server application, a library module, common settings, and the like is created, and a container for each user is created from the container template. Thereby, the process space of the accommodation user accommodated in each container is separated. This makes it possible to appropriately control resources on a container basis.

  In addition, data created by the user and customizable configuration files are secured as a data area in a storage separate from the container, the virtual storage created as a container is layered, and the data area is bind-mounted to allow the user to Can handle the file system transparently without being particularly aware of the boundary between the types of the common area (container) and the data area.

<About Container>
Here, the outline of the container will be briefly described. The container itself is an existing technology. In general, the OS is divided into a user space used by an application (software operating on the OS) and a kernel space used by the kernel. When the application is executed, a process (program execution unit) is generated in the user space. In container technology, processes are grouped and run in a space isolated from other groups and processes that do not belong to the group. This space (virtual environment) is called a container.

  In container technology, processes in a container cannot access processes in other containers. For the CPU, memory, device, etc., the range that can be used from the container is limited for each container.

  There are various types of software for creating containers (referred to as “container management software”). In this embodiment, it is assumed that Docker (registered trademark) is used as an example. ing. However, the container management software to which the present invention can be applied is not limited to specific container management software, and the present invention can be implemented by applying various container management software.

(Whole system configuration)
FIG. 1 is a diagram showing an example of the overall configuration of a system according to an embodiment of the present invention. As shown in FIG. 1, the system according to the present embodiment includes a container storage device 100 and a management device 200.

  Each of the container storage device 100 and the management device 200 is a device connected to a network, and communication between the container storage device 100 and the management device 200 is possible. Each of the container storage device 100 and the management device 200 may be one or a plurality of physical servers (computers), or may be one or a plurality of virtual servers. The container storage device 100 may be referred to as a “host”.

<Container storage device>
The container accommodating device 100 is a device that provides a shared hosting service to each user. In the present embodiment, a container for each user is created in the container accommodating device 100.

  As illustrated in FIG. 1, the container storage device 100 includes a container management unit 110, a template storage unit 120, and a monitoring control unit 130. The container management unit 110 is a functional unit for creating and updating a container based on an instruction from the management apparatus 200. In the present embodiment, functions realized by container management software, a provisioning script (program), and the like. Part.

  The template storage unit 120 stores container templates and user area templates. The container template of the present embodiment may be referred to as a container image, and is data (which may be referred to as model data) that is common between containers and serves as a template for the container. A container for each user is created based on the template, and at that time, individual user settings are made.

  The user area template includes initial settings, initial data, and the like of a user area (an area that can be rewritten by the user) in the container. The user area template itself is common between containers, but individual settings (setting file storage, etc.) are made when a container is created.

  The monitoring control unit 130 monitors the read / write frequency or data amount of user data generated as a result of execution of a process in the container, and uses a storage unit that stores user data according to the frequency or data amount. It is. Note that the monitoring control unit 130 may be a functional unit realized by a program that configures a container (that is, a program that configures a container template), or a program outside the container (a program executed by the container accommodating device 100). ) May be a functional unit realized by

  The monitoring control unit 130 also has a resource control function related to the user's use of the container. This function is based on the idea of “fair share”. Specifically, the monitor control unit 130 has a relative value and a maximum of resources (eg, CPU resource, memory resource) that each user (1 container) can use. Values are set, and the monitoring control unit 130 performs resource control based on these values.

  The relative value is the amount of resources allocated to one user. The monitoring control unit 130 limits each user's resource to a relative value when the overall load of the container accommodating device 100 is high, but if the resource of the container accommodating device 100 has a margin, the resource greater than the relative value. Is allowed. However, the maximum value cannot be exceeded. By such resource control, the entire resources of the container accommodating device 100 can be effectively used, and resources can be used equally among a plurality of containers.

  The maximum value represents a resource upper limit value that can be used by one user in a state where there is room in the resources of the container accommodating device 100. By setting such an upper limit value, even when one container goes out of control, it is possible not to occupy the resources of the entire container storage device 100.

  In other words, the monitoring control unit 130 makes it possible to use resources equally among a plurality of containers and performs resource control for limiting the resources used by one container to a predetermined upper limit value even when the entire resources are available. It has a function.

  Note that the resource control function in the monitoring control unit 130 may be realized using a container function 37 in the OS described later, or may be realized as a function different from the container function 37. Further, the resource control function may be provided as a function unit different from the monitoring control unit 130.

  The container accommodating apparatus 100 according to the present embodiment causes, for example, one or a plurality of computers to execute a program describing the processing contents in the container management unit 110 and the monitoring control unit 130 described in the present embodiment. It is feasible. That is, the functions of the container storage device 100 are realized by executing a program corresponding to the processing executed in the container storage device 100 using hardware resources such as a CPU, a memory, and a hard disk built in the computer. Is possible. The above program can be recorded on a computer-readable recording medium (portable memory or the like), stored, or distributed. It is also possible to provide the program through a network such as the Internet or electronic mail.

<Management device>
As illustrated in FIG. 1, the management device 200 includes an order management unit 210, a container storage device management unit 220, and a template storage unit 230. The order management unit 210 is a functional unit that instructs the container storage device 100 to create a container in accordance with an order from an operator or the like. In response to an update command from the operator, the container storage device management unit 220 updates the container. The template storage unit 230 stores templates of various versions, and has a function of distributing the templates to the container storage device 100.

  The management apparatus 200 according to the present embodiment can be realized, for example, by causing one or a plurality of computers to execute a program describing the processing content described in the present embodiment. That is, the function of the management apparatus 200 is realized by executing a program corresponding to processing executed in the management apparatus 200 using hardware resources such as a CPU, a memory, and a hard disk built in the computer. Is possible. The above program can be recorded on a computer-readable recording medium (portable memory or the like), stored, or distributed. It is also possible to provide the program through a network such as the Internet or electronic mail.

(Detailed example of the container housing device 100)
FIG. 2 is a diagram illustrating a configuration example of the container storage device 100 in a state where a container for each user is created. In the example illustrated in FIG. 2, each container (container 1, container 2, container 3) is generated based on the container template 10. Each container shows a common area and a user area. In the common area, a setting file 11, a library 12, and a daemon 13 are shown. In the user area, a setting file 21 and user data 22 are shown.

  Regarding "common area", it is called "common area" because it is an area (function) that provides common functions among containers such as applications (daemons) and libraries, but its operation (operation as a process) is Each container is independent. The entity data such as the setting file 11, the library 12, and the daemon (program) 13 is a container template 10 (container image). Due to the function of the container, each user is recognized to use them only. Note that the area where the container template 10 (container image) is stored is an actual “common area”, and the “common area” shown in FIG. 2 is an area having the same content as the contents of the common area. means.

  The “user area” is an area that can be rewritten by the user. Initial values of files and data in the user area are set based on the user area template 20. After the initial value is set, the user-specific setting file 21 and the like are stored (copied), whereby the user-specific setting is performed. For the user, a predetermined user data area of the file system provided by the container appears as a storage area for the user data 22, but the external area is connected to the user data area of the container by band mounting of the external area, Actual user data reading and writing is performed on the external area. That is, the substance of the user data area is in the external area. The setting file 21 may be stored in the external area by bind mount, or may be stored in the container area without performing bind mount.

  FIG. 3 is a diagram more specifically showing the configuration of the container storage device 100. As shown in FIG. 3, hardware 36 and OS 30 exist. The OS 30 may be any OS as long as it can provide a container function. For example, Linux (registered trademark) can be used. A driver 31 and a container function 37 are included as functions of the OS 30.

  The container function 37 is an OS function used for realizing the container, and includes, for example, Namespaces, cgroups, selinux, and the like.

  A management interface 34 corresponds to container management software (Docker or the like).

  In the present embodiment, the container image 33 corresponds to the container template 10. Since the content of the container image 33 becomes the content of the common area in the container, the portion of the container image 33 is described as a common area in FIG.

  In the example of FIG. 3, an example in which the container 1 and the container 2 are activated is shown. AUFS shown in FIG. 3 is one of the file system functions. All of the parent file system (container image 33 in the example of FIG. 3) is read-only, and a writable layer is overlaid on the parent file system so that one file is passed through the layer. It is a function that allows it to be handled like a file system. However, using AUFS is just an example.

  FIG. 3 shows that bind mounting is performed from an external user data area 35 storing user data for each user to a common file system directory created in each container. The user data area 35 outside the container may be provided in the container accommodating device 100 or may be provided in another device. With such a bind mount, users can access their own data from the container without being aware of the external user data area 35.

  The bind mount is a kind of mount, and is a function that allows a file path to be bound to another directory and mounted. For example, when "/ ABC / XYZ" is specified as an argument of a bind mount command, the contents of / ABC are bound to / XYZ, and the contents of / ABC are as if Looks like it exists in XYZ.

(About container creation)
FIG. 4 is a diagram showing an outline of container creation. As shown in FIG. 4, based on an order (command) from an operator or an order using an API from an order server, the order management unit 210 of the management apparatus 200 stores a container. (Container storage device 100) is determined, and container creation is instructed to the container management unit 110 of the determined container storage device 100.

  As a result, the provisioning script constituting the container management unit 110 is executed, and the container is created (activated) by using the container template and the user area template.

  The order management unit 210 includes a container management DB (database) 211. In the container management DB 211, for example, an account information table, a host information table, and an IP resource information table are stored. The account information table stores, for example, information such as account ID, accommodation host name, IP address, provisioning status (Active, Holding), domain name, contract plan, option contract, and the like.

  The host information table stores information such as a host name (container accommodating device name), a host IP address, the number of free resources, an upper limit of accommodable resources, and the like. The IP resource information table stores information such as a host IP address, a user assignment IP address, and an account ID.

  Upon receiving the order, the order management unit 210 determines, from the host information table and the IP resource information table, which host (container accommodating device) the account is accommodated in consideration of, for example, resource availability. A container creation instruction and input parameters are given to the container management unit 110 of the container storage device 100.

  FIG. 5 shows an example of a container template and a user area template. FIG. 5 shows a part of data included in each of the container template and the user area template. The container template shown in FIG. 5A includes a library, an application, an installer script, and the like. The library is an OS module, various program modules, or the like. The application is an authentication server, Web server, Mail server, mailing list server, DB server, monitoring server, or the like. The installer script is an installation package of the provided application.

  As shown in FIG. 5B, the user area template includes a setting file, a data directory, and a data file. As for the setting file, initial setting information is stored when creating a container for each user. The data directory is a directory for storing various data. The data file stores initial data.

  FIG. 6 is a flowchart illustrating an example of a processing procedure of the container management unit 110 that has received a container creation command. This processing procedure corresponds to the contents of the provisioning script. The operation of the container management unit 110 will be described with reference to FIG.

  The container management unit 110 receives, from the order management unit 210, an account ID, a password, a domain name, an IP address, a used container template ID, and the like as input parameters for a container creation command.

  The container management unit 110 creates an account based on the account ID (step S101) and creates a container (step S102). Here, a container corresponding to the container template specified by the container template ID is created. In step S102, a process of bind mounting a predetermined user data area (for example, an area identified by an account ID) to a predetermined area in the container is also executed.

  Next, the user area template is expanded (step S103). As a result, the initial data is stored in a user-rewritable area. Then, initial setting of the container is performed (step S104). Here, for example, LDAP entry creation, configuration file generation, and the like are performed. Then, container access setting (step S105), monitoring setting (step S106), and resource limit setting (step S107) are performed.

  In the resource limit setting in step S107, for example, an upper limit value of a CPU resource (eg, allocated time per unit time) that can be used by one container, an upper limit value of a memory capacity, and the like are set.

(Container update)
In the present embodiment, the container management unit 110 has a container update function (update function). The update process will be described with reference to FIG. The update is, for example, replacing the container from the old version to the new version. In addition, the container update may be performed collectively for a plurality of containers of a plurality of users accommodated in the container accommodating apparatus 100 or may be performed for each individual user.

  FIG. 7A shows a state before the container is replaced. Here, for example, it is assumed that an update command is input from the operator to the container storage device management unit 220. The update command includes information for identifying a container to be updated (account ID or container ID) and information for identifying a container template corresponding to the updated container (container template ID). The container template (new container template) corresponding to the updated container may be stored in the container storage device 100 in advance, or may be acquired from the template storage unit 230 at the time of updating.

  Upon receiving the command, the container storage device management unit 220 transmits an update command specifying a new container template to the container management unit 110 of the target container storage device 100.

  As illustrated in FIG. 7B, the container management unit 110 that has received the update command deletes (stops) the current container and updates the container template. Updating the container template may be downloading a new container template or reading a new container template stored in advance in the container storage device 100. Then, as shown in FIG. 7C, a new container is created based on the new container template.

  FIG. 8 is a flowchart showing the operation of the container management unit 110 that has received the update command.

  As shown in FIG. 8, first, the old container is stopped (step S201). Then, the new container is activated using the new container template (step S202). Similar to the container creation described above, the bind mount is also set. Similarly to the container creation described above, container access settings (step S203), monitoring settings (step S204), and resource limit settings (step S205) are performed.

  As described above, user data and customized settings are retained even if the container (that is, the common area) is replaced with an image of another template. This facilitates customization and software update work.

(User area template distribution processing example)
FIG. 9 is a diagram illustrating an example of a user area template distribution process. The template storage unit 230 stores each version of the container template and each version of the user area template. In the example of FIG. 9, for example, a new version of the user area template is distributed from the template storage unit 230 to the container accommodation apparatus 100 (A), and the user area template is applied to the container accommodation apparatus 100 (A). Further, it is shown that the user-specific setting file is copied from the operator to the setting file set by the user area template, and the individual setting is performed.

  In the example of FIG. 9, as an example, it is shown that the user area template is distributed from the template storage unit 230 to the new container storage device 100 (B) via the container storage device management unit 220. Yes.

(Example of using different user data storage)
The monitoring control unit 130 in the container storage device 100 determines the frequency of reading / writing user data (eg, the number of reading / writing per unit time), the amount of data read / written (eg: the amount of data per unit time), etc. But may be) Note that “read / write” may be “read” only, “write” only, or the total of “read” and “write”. The monitoring method is not limited to a specific method. For example, the file / directory of the file system set in the container (that is, the file / directory visible to the user) may be monitored, or the file / directory in the original area (external area) of the bind mount may be monitored. Also good.

  The supervisory control unit 130 uses data that is frequently read and written (for example, files / directories with a read / write frequency higher than a predetermined threshold) as hot data, and data that is not frequently accessed (for example, files with a read / write frequency equal to or lower than the predetermined threshold). / Directory) is used as cold data, and the target storage to be bind-mounted is properly used. As a result, high-speed storage such as SSD is used for data that requires higher I / O performance, and high-capacity and low-cost storage is used for cold data with almost no read / write. It becomes possible to use properly according to. That is, the storage resource can be controlled flexibly.

  FIG. 10 is a diagram illustrating an example in which storage is properly used. In the example of FIG. 10, since the data in the / home / user / mail directory is read and written frequently in the container, the user data area of the storage A, which is a high-speed storage, binds to / home / user / mail. Mounted. On the other hand, since the read / write frequency of data in the / home / archive / files directory is low, the user data area of storage B, which is a low-speed storage, is bind-mounted to / home / archive / files. The monitoring control unit 130 can dynamically switch the bind mount.

(Example of cooperation with external services)
An external service can be used by the container in this embodiment. FIG. 11 is a diagram for explaining the procedure.

  As shown in FIG. 11, for example, the user contracts an external cloud application such as SaaS (step S301).

  Then, the user or the operator bind-mounts the application area to be provided (server area to which the external application is provided) to the container user area (user data area) (step S302). As a result, the user can use the external service as if the application is installed in its own container without being aware of the external service (step S303).

  In addition, by describing the bind mount processing from the external service in the provisioning script that configures the container management unit 110, the container can be started in a state of being linked with the external service.

(Effect of embodiment)
In the conventional technology that shares processes among users, when some of the accommodated users occupy a large amount of resources, other users may not be able to use the service, and accounts may be hijacked. When there is an abuse, there is an effect that the response of the entire user is lowered. There is also a security concern if the software has serious bugs such as privilege escalation.

  On the other hand, according to the technology of the present embodiment, a container is created based on a template such as a server application, a library module, a common setting, etc., and the process space of the accommodating user is separated. It becomes possible to control by container unit. In addition, since the process space is independent for each container, it is possible to keep the scope of influence within the container even when individual processes are eroded for security issues.

  Moreover, in the prior art in which processes are shared among users, settings common to all users must be used. This limits the user use cases and lacks customization. In addition, among the conventional technologies, there is a service that realizes the same user convenience as shared hosting by setting up a virtual server using the cloud and managing it by a hosting company. Therefore, there is a problem that the operation cost becomes higher than the process sharing type hosting due to the increase in the amount of work.

  In response to these problems, according to the technology of the present embodiment, by securing data created by the user and a customizable setting file as a data area in a storage separate from the container, the data area is bind-mounted, The user can handle the file system transparently without being particularly aware of the boundary between the types of the common area and the data area. As a result, even if the common area is replaced with another template, user data and customized settings are retained, so customization and software update work are facilitated and operational problems can be solved.

  That is, the independence of the user's resource control can be ensured by separating the process for each user by the technique of the present embodiment. As a result, it is possible to individually deal with hijacking detection for each user, dropping a user process that exceeds the limit value, and depriving of authority.

  In addition, by setting and including a setting file in the user data area, settings and options can be customized for each user. In addition, each user's process is started for each container, but since the process is idle while the user is not using it, the disk IO and CPU resources that are the bottleneck are not consumed, so resources are used efficiently. It becomes possible to do.

  In addition, with the technology of the present embodiment, a plurality of versions of an application can be provided, and the version that the user wants to use can be selected. Executable files are installed in the common area (example: area where the entity of the container template (image) is stored), but the configuration file is placed in the user area (example: user data area to be bind-mounted). Can be overridden. That is, the setting of the user data area can be reflected.

  Also, the software update can be easily performed by dividing the user data area and the common area and replacing only the common area. That is, the user data area is perpetuated transparently to the file system and does not change before and after the replacement of the common area. Also, file differences and version management can be performed by creating a common area as a template for each release.

(Summary of embodiment)
As described above, according to the present embodiment, a container accommodation apparatus that accommodates a container that is a virtual environment that operates a specific user's process in isolation from other users' processes, Container management means for creating a container for the specific user by using model data commonly used in container creation for each user when receiving a container creation instruction for the specific user; The container storage device is characterized in that an external area outside the container is connected to a data area recognized by the specific user in the container so that data is stored in the external area. Provided.

  When the container management unit receives an instruction to update the container of the specific user to another container, the container management unit stops the container of the specific user, and stores model data corresponding to the other container. It is good also as making the said another container using.

  The container storage device monitors the frequency or amount of data read / written from / to the data area, and based on the frequency or amount of data, monitors and controls for determining an external area to be connected to the data area It is good also as providing.

  The monitoring control means determines an external area to be connected to the data area as an area in a high-speed storage when the frequency or data amount is greater than a predetermined threshold, and the frequency or data amount is equal to or less than the predetermined threshold. In some cases, the external area to be connected to the data area may be determined as an area in a low-speed storage rather than the high-speed storage.

  Further, as the external area, an area in a server that provides a predetermined application service may be used.

  In addition, the container accommodating device can use resources evenly among a plurality of containers, and includes resource control means for limiting resources used by one container to a predetermined upper limit value even when there is a surplus in overall resources. May be.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible within the scope of the claims.

DESCRIPTION OF SYMBOLS 100 Container accommodation apparatus 110 Container management part 120 Template storage part 130 Monitoring control part 200 Management apparatus 210 Order management part 220 Container accommodation apparatus management part 230 Template storage part

Claims (8)

A container accommodating device that accommodates a container that is a virtual environment for operating a specific user process in isolation from other user processes,
A container management means for creating a container for the specific user by using model data commonly used in creating a container for each user when receiving the container creation instruction for the specific user;
The container management means connects an external area outside the container to a data area recognized by the specific user in the container so that data is stored in the external area. Container storage device. When the container management unit receives an instruction to update the container of the specific user to another container, the container management unit stops the container of the specific user, and stores model data corresponding to the other container. The container container according to claim 1, wherein the container is created using the container. It further comprises monitoring control means for monitoring the frequency or amount of data that is read from or written to the data region, and determining an external region to be connected to the data region based on the frequency or data amount. The container accommodating device according to claim 1 or 2. The monitoring control means determines an external area to be connected to the data area as an area in a high-speed storage when the frequency or data amount is greater than a predetermined threshold, and the frequency or data amount is equal to or less than the predetermined threshold. 4. The container storage device according to claim 3, wherein in some cases, an external area to be connected to the data area is determined as an area in a low-speed storage than the high-speed storage. The container storage device according to any one of claims 1 to 4, wherein the external area is an area in a server that provides a predetermined application service. The resource control means is further provided for enabling the resources to be used equally among a plurality of containers and for limiting the resources used by one container to a predetermined upper limit value even when the entire resources are sufficient. The container accommodating device according to any one of claims 1 to 5. A container creation method executed by a container accommodation device that accommodates a container that is a virtual environment for operating a specific user process isolated from other user processes,
A container creation step of creating a container for the specific user by using model data commonly used in creating a container for each user when the container creation instruction for the specific user is received;
In the container creation step, the container receiving device connects an external area outside the container to a data area recognized by the specific user in the container, so that data is stored in the external area. A container creation method characterized by   The program for functioning a computer as each means in the container accommodating apparatus of any one of Claims 1 thru | or 6.

Images