Not every Arista switch is a 7050 or a 7280. This guide covers the ones that fill particular jobs: the 7010T for gigabit copper, the 7020SR for a small deep buffered edge, the 7150 for low latency with a precise clock, and the 7160 for 100GbE. It also covers the 7100 that came before them, the 7500 line cards and the Arista power supplies. Every figure comes from Arista's data sheets and end of sale notices, listed under Sources.
The short answer
Buy a 7010T for a management or out of band network of gigabit copper ports. Buy a 7020SR when a 10GbE edge needs a deep buffer: it has 3 GB. Buy a 7150 when the job is latency and timing: 380 ns on its SFP+ ports and a high precision clock. Buy a 7160 for 100GbE ports at up to 6.4 Tbps.
The models side by side
| Model | Ports | Switching capacity | Latency | Buffer |
|---|---|---|---|---|
| DCS-7010T-48 | 48 x 10/100/1000 RJ-45, 4 x 1/10GbE SFP+ | 176 Gbps, 132 Mpps | 3 microseconds | 4 MB |
| DCS-7020SR-24C2 | 24 x 10G SFP+, 2 x 100G QSFP100 | 880 Gbps, 300 Mpps | From 3.8 microseconds | 3 GB |
| DCS-7150S-64 | 48 x 1/10G SFP+, 4 x QSFP+ | 1.28 Tbps, 960 Mpps | 380 ns | 9.5 MB |
| DCS-7160-32CQ | 32 x 100G QSFP | 6.4 Tbps | From 2 microseconds | 24 MB |
| DCS-7124SX | 24 x 1/10GbE SFP/SFP+ | 480 Gbps, 360 Mpps | 500 ns | Not stated |
7010T and 7020SR
The DCS-7010T-48 has 48 10/100/1000 RJ-45 ports and 4 1/10GbE SFP+ ports, 176 Gbps, 132 Mpps, 3 microseconds of latency from RJ45 to uplinks and a 4 MB buffer. It runs on 2 supplies, 1+1, AC or DC, and draws 52 W typical and 65 W at most. The DCS-7010TX-48C, from the 7010X Series, gives 296 Gbps and 220 Mpps with latency from 2.8 microseconds in 1RU.
The DCS-7020SR-24C2 in the 7020R Series has 24 10G SFP+ ports and 2 100G QSFP100 ports, 880 Gbps, 300 Mpps, latency from 3.8 microseconds and a 3 GB packet buffer. It runs on 2 PWR-500AC supplies, hot-swap and 1+1, and draws 95 W typical and 105 W at most. The DCS-7020TR-48 has 48 RJ45 ports at 100/1000Mb and 6 1/10GbE SFP+ ports, with 216 Gbps and 162 Mpps.
7150 and 7160
The 7150S-64 has 48 1/10G SFP+ ports and 4 QSFP+ ports, 1.28 Tbps, 960 Mpps, 380 ns of latency on the SFP+ ports and a 9.5 MB buffer with dynamic allocation, plus a high precision clock. The DCS-7150S-64-CL-F and DCS-7150S-64-CL-R come with 2 AC power supplies; the DCS-7150S-64-CLD adds a 50 GB SSD and 4 GB of memory and is ordered without fans or power supplies, drawing 224 W typical and 455 W at most.
The 1RU DCS-7160-32CQ has 32 100G QSFP ports, 6.4 Tbps, latency from 2 microseconds and a fully shared 24 MB buffer, on 2 500 W AC supplies (1+1). The DCS-7160-48YC6 has 48 25GbE SFP ports and 6 100GbE QSFP ports at 3.6 Tbps, and the copper DCS-7160-48TC6 has 48 10GbE RJ45 ports and 6 100GbE QSFP ports at 2.16 Tbps.
7100, 7500 and the power supplies
The 7100 is the 10GbE switch these followed. The DCS-7124SX has 24 1/10GbE SFP/SFP+ ports, 480 Gbps, 360 Mpps and 500 ns on 2 460 W AC supplies; the DCS-7148SX has 48 10GbE ports, 960 Gbps, 720 Mpps and 1200 ns. The 7500 is Arista's modular chassis: the DCS-7500E-48S-LC is a 48 port 1/10GbE SFP+ line card with a 9 GB buffer for the DCS-7504 and DCS-7508, and the DCS-7500R2AK-36CQ is a 36 port 100GbE card with 3.34 Bpps and a 24 GB buffer.
Arista's power supplies carry their airflow in a color: RED supplies move air front to rear (FORWARD) and BLUE rear to front. The PWR-511 supplies are 500 W, AC or DC; the PWR-1011 supplies are 1000 W; the PWR-721-DC-RED is a 700 W DC supply for the 720XP; and the PWR-460AC-R is a 460 W AC supply for the 7124SX, 7050, 7150 and 7048-A.
What to check before you buy
- The F or R letter on the switch, and the RED or BLUE word on its supplies: both name the airflow.
- On a 7150, whether the unit is a CL-F or CL-R with supplies, or a CLD ordered without fans or supplies.
- On a 7500 line card, the chassis: the DCS-7500E-48S-LC fits the DCS-7504 and DCS-7508.
- The buffer the job needs: 3 GB on the 7020SR against megabytes on the 7150 and 7160.
Lifecycle: what the dates mean
Arista gives Nov 1, 2011 as the last day to order the DCS-7124S, December 20, 2013 for the DCS-7148SX and July 30, 2014 for the DCS-7124SX, and names the DCS-7150S-24 to follow the 7124SX. The DCS-7500E-48S-LC last day to order was June 20, 2019, with the DCS-7500R-48S2CQ-LC named to follow. Arista's data sheets mark the DCS-7010T-48, the DCS-7020SR-24C2-R and the DCS-7150S-64-CLD as subject to end of sale notices.
Where to look
Each family has its own page listing what is in stock: the 7010T, 7020SR, 7150, 7160, 7100 and 7500, with Arista power supplies and Arista DAC cables. Pages in stock today include the DCS-7160-48TC6-F, the DCS-7020SR-24C2-F, the DCS-7010T-48-F and the DCS-7500R2AK-36CQ. For the whole maker, read the Arista guide. Request a quote for a part that is not listed, or sell the switches you retire.
Sources
- Arista 7010T Series data sheet
- Arista 7010X Series data sheet
- Arista 7020R Series data sheet
- Arista 7150S Series data sheet
- Arista 7160 Series data sheet
- Arista 7124SX data sheet
- Arista 7148S and 7148SX data sheet
- Arista end of sale notice for the DCS-7124S and DCS-7048
- Arista end of sale notice for the DCS-7148S and DCS-7148SX
- Arista end of sale announcement for the DCS-7124SX
- Arista 7500 Series data sheet
- Arista 7500R Series data sheet
- Arista end of sale notice for 7500E line cards
- Arista CCS-720XP data sheet
- Arista 7280R3 Series data sheet
