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This article mainly introduces how to solve the common problems of Unix to Linux migration, the article is very detailed, has a certain reference value, interested friends must read it!

Identify possible hardware challenges

In the process of considering migration, the most important thing to pay attention to is platform dependency, especially the migration from RISC to X86 platform. At this point, Endianess can come in handy.

Endianess refers to the in-memory sort used to display data. It specifies how data elements and bytes are stored in memory. The problem you may encounter is that Endian is rarely used in x86 computer systems, but Endian is heavily used in RISC systems. If you migrate from RISC to x86 and vice versa, you will need to modify the migration code. During the evaluation phase, you should be clearly aware of these problems.

Some manufacturers have come up with some creative ways to solve these problems. For example, IBM developed PowerVM Lx86, a part of a medium-sized virtualization engine. It uses special software to automatically convert instructions into voltage signals, so that it does not have to be compiled on the local computer.

Although before Linux runs on the IBM Power platform, Linux must be run locally and recompiled. Of course, this is no longer a problem. As part of PowerVM Lx86, the converter can easily convert x86 Linux instructions into voltage Liunx instructions in three steps: decoding, optimization, and production code. This works well for Web applications because there is a lot of repetitive work, and because the frequently used code is already in memory, there is no need to reconvert it.

Another aspect to consider is the kernel extensions and device drivers required by the application. Finding the right kernel extensions and device drivers for applications is not an easy task, in part because most kernel API do not strictly comply with standards. API instructions, the number of parameters, and the process of calling to kernel extensions will all vary on the new platform.

Another consideration is applications that require kernel extensions and device drivers. These are not easy candidates for support, in part because most kernel API do not follow any strict standards. The number of parameters called by API and loaded into the kernel extension process will be all functionally different on the new platform.

Evaluate the applicability and effectiveness of the application to Linux

The vast majority of business and web applications can run on Linux. But effectiveness is another matter.

Although almost all manufacturers today have moved their Unix applications to Linux, the key is how to ensure that existing applications support this possible migration well before considering migration. Otherwise, you will have to fall into the dilemma of migrating these applications yourself. For internal application development, what you need is a strong development team to help complete the migration of the application.

Consult colleagues who have this experience. See what happens when your application is migrated to Linux. And verify how these applications are running now. Don't worry, please don't hesitate to ask your manufacturer for help. Both Red Hat and SUSE provide appropriate services to help you complete the migration.

Problems and errors about deployment

What kind of mistakes or problems may you encounter when you are doing a migration? First of all, proper testing is necessary. During the migration process, anything can go wrong, so you should set up a testing and experimental environment to discover and experience problems before generating the environment.

A few years ago, my team seemed to have completed an important migration very smoothly, but soon began to receive calls saying that the payroll management system was not working properly. This was a bit of a surprise, as we did unit testing, user testing, and UAT testing of the system before. It turns out that the problem is not with the migration, but because some PC clients are not compatible with older Oracle clients.

Another problem is about Unix shell scripts. One might take it for granted that Unix shell scripts work just as well on the Linux platform. Unfortunately, this assumption is not true.

Any Unix script related to an application needs to be carefully tested. The standard shell for Linux uses the Bash shell, which is built on the original Bourne shell of Unix. In our example, however, Unix uses a Korn shell. So, there must be some features that don't work correctly. Therefore, it is necessary to assume that your shell script may not work properly on the new platform. Please test each shell script you need.

Get technical support

Technical support depends on the size of your IT department and the experience of your employees. Do you have several omnipotent and experienced Linux administrators? Or they may be Unix administrators, but are they ready to accept Linux?

The level of technical support depends on the type of environment you are using. Are you running systems that can cost the company tens of thousands of dollars per minute, such as CRM or payroll?

Technical support from manufacturers is also very important. Both Red Hat and Novell provide technical support for 24amp 7. Some Unix hardware manufacturers, such as IBM, also provide their own Linux technical support.

If possible, get technical support from your hardware provider. Moreover, this will not have any adverse effect on you getting technical support from the operating system provider. Again, you need to carefully consider the economic impact of system downtime in your organization and the experience and capabilities of your employees.

These are all the contents of this article entitled "how to solve common problems in Unix-to-Linux migration". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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