bleujaegel
asked on
Flashing IOS on Cisco 2501
I have 2 2501 routers. One of which does not have the frame-relay command. I am going to backup the IOS to TFTP using the one with the command, and will restore it to the one without the command so I can complete a lab. Now when I log into router 1 and run the copy flash tftp command, it gives me the option:
Choose partition
1 read-only RXBOOT-FLH (filename is c2500-i-l-110-13)
2 read/write direct (filename is igs-in-l.110-13)
default is 1
router 2:
Choose partition
1 read only RXBOOT-FLH (filename is igs-in-l_110-22.bin)
2 read/write direct (filename is c2501.bin)
default is one.
First what is the difference between partition 1 and 2? What is RXBOOT-FLH vs. Direct? What partition am I supposed to flash? On router 1, I would have guessed partition 1 because it has the c2500 in the filename. On router 2, I would have guessed partition 2 due to the filename. Common sense might dictate that the default partition 1 is what it boots from and therefore is the one to flash. The filenames are cause for concern.
Choose partition
1 read-only RXBOOT-FLH (filename is c2500-i-l-110-13)
2 read/write direct (filename is igs-in-l.110-13)
default is 1
router 2:
Choose partition
1 read only RXBOOT-FLH (filename is igs-in-l_110-22.bin)
2 read/write direct (filename is c2501.bin)
default is one.
First what is the difference between partition 1 and 2? What is RXBOOT-FLH vs. Direct? What partition am I supposed to flash? On router 1, I would have guessed partition 1 because it has the c2500 in the filename. On router 2, I would have guessed partition 2 due to the filename. Common sense might dictate that the default partition 1 is what it boots from and therefore is the one to flash. The filenames are cause for concern.
ASKER CERTIFIED SOLUTION
membership
Create a free account to see this answer
Signing up is free and takes 30 seconds. No credit card required.
Having two partitions means that if the image file in the boot flash partition gets corrupted (just like a file in windows or any other program while open) when there is a power failure or other attempt to "break" your router, you can simply restore it from the other partition that cannot be damaged during normal operation. Rommon mode is the default bootstrap mode that your router will go into when you do not have a valid IOS image loaded. In this mode you can run basic features to load an IOS, partition the memory, set configuration register (used during password recovery), etc. So all in all even if your flash memory gets totally destroyed, you could replace the memory module and reload your IOS to the new module.
In most cases I have seen two partitions. However if you have a well managed TFTP server with all the IOS you need, then I usually only use one partition. It also depends on the memory the IOS takes up. If you only have an 8MB flash module, and your IOS takes up 6MB to load, then you can only have one partition. If the memory was partitioned to two 4MB partitions, your router would throw an insufficient memory error and send you to rommon mode. So it is always best to look at the memory requirements for an IOS you want to use from Cisco.
In most cases I have seen two partitions. However if you have a well managed TFTP server with all the IOS you need, then I usually only use one partition. It also depends on the memory the IOS takes up. If you only have an 8MB flash module, and your IOS takes up 6MB to load, then you can only have one partition. If the memory was partitioned to two 4MB partitions, your router would throw an insufficient memory error and send you to rommon mode. So it is always best to look at the memory requirements for an IOS you want to use from Cisco.
ASKER
Thanks. Got it taken care of.
ASKER