tailieunhanh - ccna study guide by sybex phần 6

. Đó là, do đó, cũng được coi là một giao thức kết nối. Kể từ khi UDP giả định rằng ứng dụng sẽ sử dụng riêng của mình bằng chi phí đường dây, mà không quan tâm đến đích. Tuy nhiên, nếu bạn muốn đảm bảo rằng tất cả các gói tin được gửi đến một địa điểm hoặc | Backing Up and Restoring the Cisco IOS 339 Before you begin make sure that the file you want to place in flash memory is in the default TFTP directory on your host. When you issue the command TFTP will not ask you where the file is. If the file you want to restore is not in the default directory of the TFTP host this procedure won t work. Copying the IOS from the TFTP host to flash memory requires a router reboot. So instead of upgrading or restoring the IOS at 9 . on Monday morning you should probably wait until lunchtime. After you enter the copy tftp flash command you will see a message informing you that the router must reboot and run a ROM-based IOS image to perform this operation Router copy tftp flash NOTICE Flash load helper This process will accept the copy options and then terminate the current system image to use the ROM based image for the copy. Routing functionality will not be available during that time. If you are logged in via telnet this connection will terminate. Users with console access can see the results of the copy operation. ---- ----- Proceed confirm press enter After you press Enter to confirm you understand that the router needs to reboot the following router output is displayed. Once the router has used the TFTP host it will remember the address and just prompt you to press Enter. System flash directory File Length Name status 1 8121000 8121064 bytes used 8656152 available 16777216 total Address or name of remote host press enter Copyright 2000 SYBEX Inc. Alameda CA 340 Chapter 7 Managing a Cisco Internetwork The next prompt is for the name of the file you want to copy to flash memory. As noted earlier this file must be in your TFTP host s default directory. Source file name Destination file name press enter Accessing file on . Loading from via Ethernet0 OK After