Case description

the customer reported to us that the Storage server of their DELL SCv/EMC SC E10J model (4020) failed. After logging on to the controller, the customer prompted the Storage Center to shut down and all data could not be accessed, hope to help them recover their data.

Solution

1. Case assessment

1) phenomenon description

after you log on to the Storage Center of the Dell server, you cannot access the Data. All the divided Storage spaces are reported as errors. The Storage Center is shut down and the connection is incorrect. The Data Collector cannot communicate with the Storage Center:

2) cause analysis

there are generally two possibilities for this failure:

first, there is a problem with the Dell Storage Manager Client system. This kind of failure can be understood as the general desktop computer system is damaged and cannot start normally. Similarly, Dell SCv/EMC SC series storage also has its own built-in system, after the system crashes or problems occur, you can log on to the system interface but cannot access any information;

the second is that the hard disk fails, and the system cannot be accessed due to the hard disk failure. Three hard disks need to be damaged at the same time, or three hard disks need to be offline for unknown reasons at the same time. Users can find out in time if they don't use them, or did not give the user the time to replace the hard disk.

2. Recovery plan

1) if it is the first failure of system damage, you can contact Dell's after-sales maintenance personnel, who will reinstall the system, because the system is divided into outer layer and inner layer, if the hard disk itself is not damaged due to system damage, you can directly reinstall the system. After The reinstallation, the system will automatically access the inner layer so that you can directly access the data storage layer, as shown in the figure:

as you can see, after the storage system is reinstalled, you can normally click the space that has been divided below. The reason why the icon with X reports an error is that the storage system is directly removed and reinstalled, in this case, there are two recovery ideas: one is to directly re-connect the storage to the connection according to the previous interface, because the internal structure has not changed, connect directly to the server or switch according to the previous wiring method, and it can be used normally. The second is to reconfigure the host configuration of the Dell Storage Manager Client, and hang the divided space on the system to be used through the HBA and FC for data extraction or direct use.

2) if the hard disk is damaged, the damaged hard disk needs to be physically mirrored to the new hard disk. If the hard disk has Verification, skip the verification and perform sector-control mirroring, that is, skip the verification information of the faulty disk and keep the verification information of the new hard disk for mirroring when writing. If the hard disk sector is not seriously damaged, the new hard disk that is re-mirrored will be connected to storage according to this method, and the hard disk can be reconfigured after restarting. If the hard disk sector is seriously damaged and the virtualization information on the three bad hard disks is not mirrored, then the original storage cannot be used normally. In this case, all the hard disks need to be removed, manually analyze the virtualization information of all hard disks through professional tools, then reorganize the array structure of distributed storage, and finally extract data.

Case Summary

DELL DELL SCv/EMC SC series Storage Center has many Storage server models, timely after-sales service and high cost performance, so it has been selling well in China. However, the standard warranty for Dell servers is only three years, and three years later is the beginning of the high frequency of server failures. The Marine Super standby technical team summarized the common faults of Dell servers as follows through the accumulation of past case experience: 1. The server does not boot, black screen, blue screen, card boot LOGO screen; 2. Server motherboard damage water inflow, lightning strike, overvoltage, Motherboard aging damage, etc.; 3. Server array information is lost; 4. The server's hard disk is lost or the hard disk cannot be restored. 5. The power supply of the server is damaged; 6. The operating system of the Dell server is damaged.