Using C9300 as a Core switch

[cyh]

I’m not too much into network. Can C9300 be used as a Core switch in a stretch network? What feature is lost compared to C9400?  https://www.router-switch.com/media/upload/product-pdf/cisco-catalyst-9000-switches-comparison-9200-vs-9300-vs-9400-vs-9500.pdf Checked this, but no idea what "core" differences. C9400 do have dual supervisors. 

Why/when “traditional core” is needed?  thanks!

[Leo Laohoo]

---

@cyh wrote:

Can C9300 be used as a Core switch in a stretch network?

---

In the simplest of term, and without knowing exactly what your network is like, the answer is "yes".  9200/9200L, 9300/9300L can be used as a core switch in a flat network. 

---

@cyh wrote:

C9400 do have dual supervisors. 

---

That's not a reason enough.  9300/9300L can have up to 16 supervisors:  Each switch member can be a master switch and the 9300/9300L can support between 8 (official Cisco documentation) to 16 switches (un-official) in a stack.  

Difference between a stacking switch vs a chassis-based switch?  Stability:  9200/9200L, 9300/9300L have stability issues with the stacking modules.  9400 does not have "stacking" running in the background so it does not have the same issue as switch with stacking.

[cyh]

Thanks, I don't know about the stability issue of stacked switch. I'm concern about features which C9300 don't have which affect it being a Core.

The network is basic, stretch between 2 datacenters, lease few racks for <9 servers and 1-2 storage. The design is for 2 x C9400 per datecenter, for redundancy. I'm thinking of one C9400-7 per DC would be enough or 3-4 stacked C9300. Since C9400 have 2 supervisors and card can be swap out online.

[balaji.bandi]

The answer is YES/ NO - YES depends on the requirement "definition of CORE here," how big your network. and what kind of processing requirement.

I have seen some small companies' few stack switches, they used Cat 9300 as core and Cat 9200 or Cat 9300 as Access switches.

There is some Limitations in Cat 9300 (which can not act as Cat 9500 or Cat 9600 or replace featured of those devices.), that can be verified by features.

https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9000/nb-09-cat-9k-aag-cte-en.html

[cyh]

Thanks Balaji, mainly to connect 2 datacenters which we will lease few racks. < 9 servers + 1-2storage, requirement is for data to be synchronized between site. Data sync can be via hyper-converged infrastructure or storage replication. The selected devices are 2xC9400-7 per site with 2 cards. So, I wonder can it be one C9400 or few stacked C9300 instead.

[balaji.bandi]

I have addressed other posts some concerns.

[Leo Laohoo]

---

@cyh wrote:

Thanks Balaji, mainly to connect 2 datacenters which we will lease few racks. < 9 servers + 1-2storage, requirement is for data to be synchronized between site. Data sync can be via hyper-converged infrastructure or storage replication. The selected devices are 2xC9400-7 per site with 2 cards. So, I wonder can it be one C9400 or few stacked C9300 instead.

---

I have already responded to your other thread about the 9400 doing DC switching. 

Catalyst switches are not ideally suited for DC switching but it does not stop people from buying and installing them in this environment.  

Catalyst switches cannot support DC downstream clients without configuring QoS while dedicated DC switches, like the Nexus family, which can support DC clients at line rate without any need of QoS.  Configuring QoS, in my opinion, in Catalyst switches to accommodate DC clients would be like setting the ports to 100 Mbps.