How many smart crossover cables needed for 3 x WIC-2T's CCNA R/S study please

sferg410 wrote: »

OK, I now have ordered my 3 WIC-2Ts for £38 total. I just want to check one final thing, how many smart crossover cables do I need, I am assuming 3, is that correct?
These leads are the last things i need to order.
Thanks

Two. One goes port1 on R1 to port1 on R2, and the other goes port2 on R1 to port1 on R3. I don't believe you're making a fully redundant topology for frame relay like you probably would with your switches for other modules.

GDaines wrote: »

I don't believe you're making a fully redundant topology for frame relay like you probably would with your switches for other modules.

OK. Understood that until the second part!!!

Did you also get my PM GDaines that you asked for?

sferg410 wrote: »

OK. Understood that until the second part!!!

Did you also get my PM GDaines that you asked for?

Okay well I'm not going to get in to redundancy and all that, you'll understand one day, and yes I got your PM which I hope you don't mind me reposting as the answer will be useful to some people.

sferg410 wrote:

Hello, this is the ebay links to the memory I bought. You will probably write back now and tell me it is the wrong stuff!!!!
Corsair 4 x 512MB = 2GB PC2700 (333), 184PIN, DDR1 Desktop RAM Memory NEW SEALED | eBay

Sadly yes, it does appear that you've bought the wrong stuff, though in your defence I do recall someone answering one of your posts and telling you that you must absolutely NOT buy cheap server ram as it's ECC and so wouldn't work.

Well, that was bad advice! I did a Google search for "Cisco 2811 memory" and the first entry was this 512mb module from Offtek for £23.88 delivered. Thing that stood out the most was the specification which reads "184 Pin 2.5v DDR266 ECC Dimm". So I did a search in eBay and noticed that no-one lists the spec, they just say it's memory for a 2811. Next I looked for the appropriate Cisco page where I found this which states quite clearly ECC...

As one of my 2811's isn't properly mounted I decided to open it up and take a look and indeed it has 256mb ECC ram fitted...

And finally to be sure it works I plugged it in and booted it...

Cisco 2800-series memory.jpg

P1050707-1280x960.jpg

2811 running ECC ram.jpg

what about "512MB DDR, 266, CL2, ECC, REG DIMM"

what is the difference between what the Cisco uses and this memory below?
http://www.ebay.co.uk/itm/Micron-MT18VDDT6472G-265C3-512MB-Server-Memory-RAM-PC2100R-25331-Z-/152035683497?hash=item2366086ca9:g:Q~YAAOSwxcRW~QJP

yes i told him that he will not be able to use server ecc memory. But, it isn't because it is ecc. Server memory is buffered (or registered). Cisco uses ecc memory that is unbuffered.

no that memory will not work. The REG stands for registered. It will work in a server but not in your 2811.

While the 2811 comes with ecc memory. non-ecc memory will work just fine also. and is a lot cheaper than ecc memory that runs in cisco equipment

yes that desktop memory will work for you. of course you cant mix ecc and non ecc in the same piece of equipment

clarson wrote: »

yes i told him that he will not be able to use server ecc memory. But, it isn't because it is ecc. Server memory is buffered (or registered). Cisco uses ecc memory that is unbuffered.

no that memory will not work. The REG stands for registered. It will work in a server but not in your 2811.

While the 2811 comes with ecc memory. non-ecc memory will work just fine also. and is a lot cheaper than ecc memory that runs in cisco equipment

yes that desktop memory will work for you. of course you cant mix ecc and non ecc in the same piece of equipment

Just to confirm, you are saying the memory I have bought already (link below) will work????
Corsair 4 x 512MB = 2GB PC2700 (333), 184PIN, DDR1 Desktop RAM Memory NEW SEALED | eBay

yes it will

you'll get a message at startup telling you the memory installed is non-ecc. other than that, it will work just the same. at least until you get a memory error, which shouldn't be for years if ever.

clarson wrote: »

yes it will

you'll get a message at startup telling you the memory installed is non-ecc. other than that, it will work just the same. at least until you get a memory error, which shouldn't be for years if ever.

Fantastic.... Will it be worth getting 3 x 256MB to max out the memory for IOS 15.1????

well here are some considerations.

1 2811 can have a maximum of 768b of memory
2 there are only 2 slots for adding memory
3 the biggest memory stick is 512mb
4 the maximum your ever going to need in a lab is 512mb
5 don't know what they will come with, but probably 256mb if ecc memory. Cisco only uses ecc memory in it's 2811. So, if you add non-ecc memory and try to sell the router, you should tell the purchaser that the memory is non-cisco.
6 you can't mix ecc and non-ecc memory. While you can pull one ecc memory stick from one router and add to another router that has ecc memory to make 1 router with 2 sticks of ecc memory. That leaves you with one stick of ecc memory and no other ecc memory to match up to it. So, the last two routers will have all non-ecc memory installed with 1 or 2 sticks of 256mb or 512mb memory sticks. Save that last ecc memory stick for your next 2800 router if you purchase another.

The 512mb memory sticks will be more than enough for a lab.

Useful info clarson, I saw that the new memory he linked to was Registered and didn't think that would work, but I didn't put two and two together to realise that Cisco uses non-registered ECC while all (?) server memory will be Registered ECC. I also didn't know they'd boot up okay with non-ECC and just throw up an error.

So to put it in simple terms sferg410, take the ECC memory out of two routers and fit a 512mb stick of what you've bought into each of them, then put one of the sticks of 256mb ECC you've just taken out into the third router so it has two sticks, then they'll all have 512mb. Don't know what will happen if you fit two sticks of 512mb, it's gonna be one of three possible outcomes (feel free to test and tell us):

1. It refuses to boot until you take one out.
2. It boots but only shows 768mb.
3. It boots and doesn't even see the second stick so only shows 512mb.

OctalDump

GDaines wrote: »

Useful info clarson, I saw that the new memory he linked to was Registered and didn't think that would work, but I didn't put two and two together to realise that Cisco uses non-registered ECC while all (?) server memory will be Registered ECC. I also didn't know they'd boot up okay with non-ECC and just throw up an error.

Yeah, unregistered (UDIMM) ECC or nonECC will work in the 2800s. The 1841 uses non-ECC SODIMM. For a lab the ECC isn't a big deal. If you had something in production running 24/7, you can see that ECC could be useful.

As far as servers go, from this vintage only some will use unregistered, and ECC UDIMMs are more likely "workstation RAM". More recent servers, particularly small ones, often can take either (but not both) either officially or unofficially. Sometimes unregistered RAM with ECC will still be described as 'server RAM' or 'workstation RAM'.

If you are buying from eBay, then the keywords are UDIMM, unregistered or unbuffered. Unfortunately, a lot of sellers on eBay aren't 100% accurate with terminology, so it can be worth looking up the actual part numbers. Registered RAM will generally be fairly easy to pick visually, since it has controller chips as well as the DRAM chips. ECC will have 9 (or 1

DRAM chips vs 8/16 for non ECC.

GDaines wrote: »

Useful info clarson, I saw that the new memory he linked to was Registered and didn't think that would work, but I didn't put two and two together to realise that Cisco uses non-registered ECC while all (?) server memory will be Registered ECC. I also didn't know they'd boot up okay with non-ECC and just throw up an error.

So to put it in simple terms sferg410, take the ECC memory out of two routers and fit a 512mb stick of what you've bought into each of them, then put one of the sticks of 256mb ECC you've just taken out into the third router so it has two sticks, then they'll all have 512mb. Don't know what will happen if you fit two sticks of 512mb, it's gonna be one of three possible outcomes (feel free to test and tell us):

1. It refuses to boot until you take one out.
2. It boots but only shows 768mb.
3. It boots and doesn't even see the second stick so only shows 512mb.

I don't think I will end up with any 256mb boards from the Cisco router as I think the place I am buying them from will install 15.1 on the router with enough memory and flash and then remove said memory and flash and replace with a much lower amount to keep the unit price down for me as I have told them I will have 512mb memory boards and 256mb cisco flash memory.

So I will be removing all memory from all 3 routers and replacing with 1 x 512mb board and 256mb flash in each. Leaving me with 1 x 512mb board left over.

My further question was whether there is any point in getting 3 x 256mb boards for about £5 or less to max them out at 768mb or if there is simply no benefit to that? Was 3 x 256mb boards on ebay auction yesterday with no bids and would of ended up costing about £2.50!! Listing seems to have changed now and only 1 board available.....

I will of course let you know if it all works ok when I have everything and take a nice picture or two for you all.

sferg410 wrote: »

I don't think I will end up with any 256mb boards from the Cisco router as I think the place I am buying them from will install 15.1 on the router with enough memory and flash and then remove said memory and flash and replace with a much lower amount to keep the unit price down for me as I have told them I will have 512mb memory boards and 256mb cisco flash memory.

Presumably they'll supply them with ram in which case it's likely to be the minimum/default 256mb, I'd be surprised if they ship them with none. And the IOS loads from flash so they'll have to supply you with a least one with the IOS 15.1 image which you could then backup (or some other method of giving you a copy of the IOS image like CD/DVD/USB), and then restore that IOS image to each of your routers (flash cards).

As far as I know they will put 15.1 on all 3, but if it is on the card then I guess i will need to recopy it anyway. How do you copy the IOS from one flash disk to another?
I will be talking with them tomorrow about the routers so will know more then. He mentioned about it running a bit sluggish until I put my upgrades in but cant remember what amount of memory and flash they said they will send.

sferg410 wrote: »

I don't think I will end up with any 256mb boards from the Cisco router as I think the place I am buying them from will install 15.1 on the router with enough memory and flash and then remove said memory and flash and replace with a much lower amount to keep the unit price down for me as I have told them I will have 512mb memory boards and 256mb cisco flash memory.

So I will be removing all memory from all 3 routers and replacing with 1 x 512mb board and 256mb flash in each. Leaving me with 1 x 512mb board left over.

My further question was whether there is any point in getting 3 x 256mb boards for about £5 or less to max them out at 768mb or if there is simply no benefit to that? Was 3 x 256mb boards on ebay auction yesterday with no bids and would of ended up costing about £2.50!! Listing seems to have changed now and only 1 board available.....

I will of course let you know if it all works ok when I have everything and take a nice picture or two for you all.

Well that isn't quite what they are going to be doing. a 2811 has 256mb of ram as a minimum and most versions of the 15.0 ios require a 128mb flash. So, 256mb and 128 flash is the minimum that people will buy. So, they are just pulling the standard units that they sell off the shelf. and that amount of memory will work just fine for the ccna. You really only need the 512mb and 256 flash for doing voice. And, there is no need to upgrade the memory to 768 at all.

for copying, I'd suggest copying the ios to a tftp server. Then copying from the tftp server to the flash cards. You could also use a usb drive. or also a card reader on a computer. unfortunately, with a 128mb cf, you really can only put one ios file on it at a time. So, the ios is running in ram, you need to erase the old ios and copy the new ios onto the cf. So, you end up with a cf with one version of the ios that has been untested. And, you don't know if your copy was corrupted until you boot it up. And, then if it was corrupted, you have to setup rommon to copy from a tftp server. no fun there. That is why a 256mb flash is nice to have. you can put multiple ios files on it. So, you can keep the old version until the never version has been tested to at least boot up.

Well I will have 3 x 256mb flash cards, already have one here, 2 more on their way and there will be whatever comes with the routers. Any way I can get one of you guys to get the IOS onto the 256mb flash cards some how?
I assume you cant just have the IOS running on one router, put a blank 256mb into a 2nd router and read it with the first router like it is just another drive as you would when accessing an HDD plugged into another computer on a small home network and then copy the files accross?

well yes you can.
set up connectivity between the two routers on the same network.
set up router1 to be tftp server for the ios file (or have your pc be the tftp server)

The external CF memory card should not be removed if the flash memory busy “CF” LED on the router is ON, because this indicates that the software is accessing the CF memory card. Removing the CF memory card may disrupt the network, because some software features use the CF memory card to store tables and other important data.

on router2 remove the cf and put the new one in
tftp the ios file to the flash in router 2
put the old cf card back into router2
and hope nothing goes bad.

What i'd recommend is getting a cheap usb cf card reader (and write) for your pc. Then, tftp the ios file to your pc. Then, on your pc copy the ios file to the flash card via the usb reader.