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wayratel
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CRS328-4C-20S-4S+RAM upgrade

Tue Jun 26, 2018 1:41 pm

Hi can I increase the RAM of the above named from 512 to 2GB
 
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chechito
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Re: CRS328-4C-20S-4S+RAM upgrade

Wed Jun 27, 2018 10:11 pm

Hi can I increase the RAM of the above named from 512 to 2GB
what would be the purpose of doing that to a switch ???

switch is a networking device who makes packet switching by hardware, that means using an ASIC (Application-Specific Integrated Circuit)

that ASIC does not require large amounts of memory of a big CPU to do his job

Included CPU and RAM on CRS products are there to manage the device
 
wayratel
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Re: CRS328-4C-20S-4S+RAM upgrade

Thu Jun 28, 2018 10:34 am

I thought CRS can dual boot as Router or Switch I was thinking of increasing RAM and use for routing
 
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chechito
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Re: CRS328-4C-20S-4S+RAM upgrade

Thu Jun 28, 2018 11:09 am

I thought CRS can dual boot as Router or Switch I was thinking of increasing RAM and use for routing
512mb included ram is enough for routing with 800mhz single core cpu included

dont expect good routing performance with such a small CPU

managing switch takes some % of the already scarce CPU resources
 
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normis
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Re: CRS328-4C-20S-4S+RAM upgrade

Thu Jun 28, 2018 11:13 am

No, you can use it with RouterOS or SwitchOS, but both of them for switching. RouterOS can also be used to configure the ports for switching, it doesn't mean the device will become a router. If you need a router, I suggest to look at the CCR series of devices.

The CRS can be used for some routing tasks, but the CPU was not made for that, and will not be great at this task if you do it with many ports.
No answer to your question? How to write posts
 
wayratel
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Re: CRS328-4C-20S-4S+RAM upgrade

Fri Jun 29, 2018 1:20 pm

ok will use CCR for routing. I plan to do 60km fiber link using CCR1016-12S-1S+ at data centre and CRS326-24G-2S+RM at emote site.Do think I can pass 10G traffic over 60km link?if yes what SFPs do recommend
 
DJSmiley
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Re: CRS328-4C-20S-4S+RAM upgrade

Mon Jul 02, 2018 10:32 pm

No problem usually, but it depends on your link loss.

Are using WDM? In those cases you have to included the mux losses as well.

As a general rule: Any 80km optic usually will work, but you can only confirm this for sure if you know the line loss.
 
wayratel
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Re: CRS328-4C-20S-4S+RAM upgrade

Tue Jul 03, 2018 9:16 am

Hi we are not using WDM we will try with BIDI SFPs
 
DJSmiley
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Re: CRS328-4C-20S-4S+RAM upgrade

Tue Jul 03, 2018 9:57 am

Why bidi?

Attenuation is usually specified for 1310 and 1550nm wavelengths.
1310nm has a higher attenuation compared to 1550nm, depending on the fiber type. Bidi uses 1270/1330nm, so even if you have sufficient power budget to establish link, there is less remaining budget to compensate for small fiber issues.
On a 60km link this would make a difference of 8-10dB (estimated) between 1310 and 1550nm. I even doubt if bidi is possible, with an average attenuation of 0.4dB/km at 1310, your link loss will be 24dB, which IS your total power budget. No addtional patch losses are included, so your link is likely to run on or out of its specifcations, unless your fibers have better specifications. But for long distance links, I've never seen usage of bidi optics.

Also:
You can't amplify signal if you need to cover some more fiber length
You only have 1 link available, no redundancy in optics or additional bandwith
You have to stock 2 pieces since both sides use specific optics (1270/1330 for side A, 1330/1270 for side B)

I highly recommend buying DWDM optics. They are not that much more expensive, but gives you much more value on the long term: You can add addtional wavelenghts to get 20Gbit (and no loss of link if a optic dies when using 2x10Gbit combined, only some loss of capacity).
Also, you can easily regenerate wavelenghts if needed, or use OADM if you need connectivty somewhere within the fiber path.
Finally, you only have to stock 1 optic as spare in case of issues instead of a set of 2. (Off course when using multiple lengths, you need to have stock for all used wavelengths)
Even if you're not using DWDM yet, you still can use them and add a mux/demux when needed at a later time.

With bidi you'll have the link (depending on the fiber type), likely running at its bottom specs, and thats all. No other options for future needs, you will have to replace them. And for 60km, there is also very little of no room for any fiber degradation or the link will run out of the specs and cause packet loss.
 
wayratel
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Re: CRS328-4C-20S-4S+RAM upgrade

Tue Jul 03, 2018 10:15 am

Thanks for advise do have any particular brands that you can recommend maybe a site where I can order

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