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Cisco 1721

CodeBlox

This was my first time purchasing a router. While it only has the 56k WIC interface, I have learned some things from it. When I got it in the mail today, the thing would not boot. So I learned how to use XModem command. I also realized how slow it was. It was going to take 2 hours to transfer a 5mb file -_- through the rollover cable. So then I learned how to use the TFTPDNLD command. Pretty friggin cool as I never knew how to do this stuff. The router would not boot when I got it, so I had to recover IOS from a copy on my computer for this router. After that, it worked. But my question for this thread is, was this a good buy? It didn't have any serial interfaces so I'll have to buy them myself. It costed 9 bucks on ebay but there was like 10 dollars shipping. Also, I am surprised at how quiet this thing is. The ones that I've used in the lab at school (2911s) were sorta loud and you could hear the fans blowing inside of them. I don't think the fan in this one is broken, but I hear absolutely nothing while it's running and it generates no heat at all. If not for the (LED?) lights I wouldn't be able to tell if the thing were on or not. Anyway, was this a good buy?

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Comments

MAC_Addy

Since it was so cheap I don't think it was a bad buy, and you learned a few new commands out of it too! Best thing to do is take the top off and make sure the fan is installed and is also working.

Slowhand

It was definitely a good buy, I picked up four 1721's for the same price about three years ago, or so. As long as you have 64MB of flash memory on the device, you're golden. It maxes out at 128MB of RAM, so you might need to upgrade that if you want to use any of the larger IOS 12.4 or 12.4T images. As for what it can do, have a look at the Cisco Feature Navigator and search for the 1721 platform.

Slowhand

Oh, I forgot to mention, they are pretty quiet routers. Mine don't make a whole lot of noise either, all four run practically silent.

CodeBlox

I'm a little confused between flash memory and dram. The flash memory is not upgradeable right? DRAM IS correct? Does IOS get pulled into DRAM in a larger size as if uncompressed? DRAM is volatile so I wouldn't think IOS would be stored there. I opened this thing up. I saw an empty slot for what appeared to be RAM. That's what I'd be adding the stick to if I were to upgrade the hardware right? Looks like it has 32mb of flash memory. Not sure about how much DRAM as the slot is empty.

According to this: Installing and Upgrading Memory in Cisco 1700 Series Routers - Cisco Systems

I have the 32mb of flash memory along with 64mb of DRAM. Someone, shed light please! I thought IOS was stored in flash memory. Sure is where it was stored when I copied it over. So does it get uncompressed and put completely in DRAM?? Going by this, all IOS's would need to be smaller than 32mb originally.

Edit: Looking at this motherboard, it looks like there is ram built into the motherboard. Would this be the case? Cause I don't see any sticks of RAM but there is a spot in the corner and it looks like RAM is built right into this mobo. First time seeing the inside of a router so sorry if this sounds totally noobish haha. But there are some familiar things, looks like there are jumpers on here too.

Also, the fan is installed onto the top of the inside of this case and is plugged into a port on the board.

CodeBlox

Looks like this question has been asked before here. Seems that flash is not upgradeable. My next move is to add a 64mb stick of DRAM and it will be 128mb of ram and 32mb flash.

alxx

The 1721's , 1751's are good small routers , and unlike most other cisco ones are almost totally silent
and don't suck to much power.

The ram for the 1700's is the same as the 2600xm's.

1751's have slots for the PVDM (dsp modules for voip)
The 1760's are similar except are rackmountable , are also voip capable (with PVDM) and take flash simms

1751
Cisco 1751 Modular Access Router* [Cisco 1700 Series Modular Access Routers] - Cisco Systems

1760
Cisco 1760 Modular Access Router [Cisco 1700 Series Modular Access Routers] - Cisco Systems Cisco 1760 Modular Access Router Hardware Installation Guide - Installing and Upgrading Memory and Packet Voice Data Modules [Cisco 1700 Series Modular Access Routers] - Cisco Systems

ChooseLife

At $20, it sure is a good buy, especially considering IOS restoration experience you got out of it

Slowhand

CodeBlox wrote: »

Looks like this question has been asked before here. Seems that flash is not upgradeable. My next move is to add a 64mb stick of DRAM and it will be 128mb of ram and 32mb flash.

Scratch what I said above, the max flash memory for the 1721s is 32MB, so you're good there. Apparently, I didn't have enough coffee earlier today.

docrice

I use a 1721 as my border router at home. It has a ADSL WIC in it so I don't have to use a separate DSL modem. These are older models for sure, but it gets the job done and as something that sits in front of my ASA, I think it's great for home use. I don't care for the brick power supply, but that's just me finding something to complain about.

alxx

Not that I need yet another 1721 , after picking up a couple with wics for 0.99ea a few weeks back (have 4x1721's, 2x1751's, 4x2600xm's,3x1760,1x1841 ,1x3640 and a 3669 + plenty of switches) but if only I could organise transport.

1/3 rack + 1721 for 0.99
Cisco 1721 With ADSL & Netgear FS516 & More In Cabinet Rack Look Pick Up Only | eBay