2600's IOS NVRAM

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2600's IOS NVRAM

Yeti-GBR1
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2600's IOS NVRAM

Ok I have changed the config on this router from confreg 0x2142 to confreg 0x2102
---------------------------------------------

cisco 2620 (MPC860) processor (revision 0x100) with 18432K/6144K bytes of memory
.
Processor board ID JAB02490083 (3321208886)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
1 FastEthernet/IEEE 802.3 interface(s)
4 ISDN Basic Rate interface(s)
32K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102
---------------------------------------------
My question is why is the System Flash still in (Read/Write) mode? Is this normal for 2600's?

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01-23-02 10:11 AM

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peterd
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Hi,

I have a couple of 2600's on my network and they show the same as yours. I think the 2600 is like the 1600 and it unzips the file before it's used (BICBW!), maybe that's why it stays in this mode?

Regards
Peter

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01-23-02 10:48 AM

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Yeti-GBR1
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Hmmm makes sense if it needs access to the file system.

Cheers Pete

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01-23-02 11:32 AM

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MadChef
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Re: 2600's IOS NVRAM

quote:
Originally posted by Yeti-GBR1

My question is why is the System Flash still in (Read/Write) mode? Is this normal for 2600's?

Yes. This is how copy tftp flash works without reloading the router.

MadChef

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01-23-02 05:04 PM

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Yeti-GBR1
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I know you need it when you are UP-LOADING an IOS image, but in a running environment I'd prsume it to be read only ...UNLESS it is its normal state, otherwise its a HUGE security risk. (even I'm not that much of a dweeb )

So far no one has verified that (READ/WRITE) 2102 is the normal state nor provided evidence.

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01-23-02 05:55 PM

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dmaftei
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Re: 2600's IOS NVRAM

quote:
Originally posted by Yeti-GBR1
Ok I have changed the config on this router from confreg 0x2142 to confreg 0x2102

Changing the value of the config register has nothing to do with the RW/RO state of the flash. You changed bit 6 (the "ignore NVRAM contents" bit) from 1 (ignore) to 0 (don't ignore). You didn't "touch" the system flash...

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01-23-02 06:09 PM

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Yeti-GBR1
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Ok so when you do the self same thing on a 2500 why does the flash change its state form read only to read write?

I understand what each hex digit does, is it because the 2600's run a different IOS to the 2500's ie the architecture is diffrent so it reacts differently? Or am I worrying about nothing and barking up the wrong forest track?

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01-23-02 06:21 PM

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dmaftei
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quote:
Originally posted by Yeti-GBR1
Ok so when you do the self same thing on a 2500 why does the flash change its state form read only to read write?

When you do what same thing? Changing the config register from 0x2102 to 0x2142 and the other way around? I doubt the system flash changes its ro/rw status when you do it. In both cases the router boots the full IOS system image from flash. You're probably thinking of 0x2101, which prevents the router to boot the IOS -- the router remains in rxboot mode. In this mode the flash is read/write.

quote:
...is it because the 2600's run a different IOS to the 2500's ie the architecture is diffrent so it reacts differently?

Yes.

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01-23-02 07:56 PM

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Yeti-GBR1
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Yip its official...I'm a Dweeeeb

Cheers dmaftei, looks like I was lost in the forest with out a compass.

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01-23-02 08:42 PM

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