According to TCAM table available entries are running out on my switch soon. I’ve been struggling to change a TCAM template on a box 7050 for few days and try to have a look any resource of Arista ASIC architecture but they all were not matter to change a template of ASIC. And look like Arista allows only FIB and RIB are able to be customized in this case when I tried. Take a look captures below.
Does anyone know how to deal with this one? My purpose is to change allocation of TCAM template not FIB or RIB.
Thank you in advance!!
Well, the FIB is related to the TCAM.
Talking about "hardware tables" in general can be a long discussion, the FIB is a part of the TCAM or hardware tables. Some platforms have got dedicated tables for specific roles, to optimise the space, cost and scale, but in the case of the Trident-family of chips it is a universal hardware table; TCAM.
Sorry the term "forwarding-table" might bring confusion, but it is indeed the TCAM, the data-plane, the hardware table that also involves the ACLs, QoS, PBR, etc
What exact model is that? 7050s or 7050SX?
The 7050X-series uses a modular TCAM as a Unified Forwarding Table (UFT).
More details here: https://www.arista.com/assets/data/pdf/Whitepapers/Arista_7050X_Switch_Architecture.pdf
7050X#show platform trident forwarding-table partition
Does the answer the question and clarifies the terminology?
Nowadays most of the modern network processors or network ASICs are doing the forwarding in hardware, so "fast forwarding" is always happening in the data plane: the CPU/software is never involved in any transit forwarding decisions. So it's always "fast".
In the past, some of the tables were held in software by legacy switches, and only installing in hardware a portion of the tables. A lot of forwarding was still done one software.
Nowadays there is none, everything is in hardware. Todays' hardware line rate capacity at L2/L3 is 12.8Tbps per chip; at time of writing.
On the Trident-family (X-series switches), There is only one forwarding table, only one TCAM, one hardware table split among different features, so effectively TCAM ~= FIB ~= hardware table.
The command you mentioned DOES change the hardware table, DOES change the TCAM, DOES change the FIB.
The TCAM allocation WILL be changed by this command, reallocating the hardware resources to the different features
The allocation differences are listed in the command output you provided.
I hope this clarifies.
Excellent job!! Appreciated your time,
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