Two switches are planned to be replaced (old hardware and I prefer have the
same management for the hardware).
The rack-space is not an issue (plenty of room) and one 24port switch might
(just) be enough, but then there would be a lack for quick expansion.
I am looking at 2 * CRS326-24G-2S+RM or one CRS354-48P-4S+2Q+RM
Electricity
When I disable the ports not in use on a 48p switch, does it actually consume electricity?
In other words, when about 50% of the ports of CRS354-48G-4S+2Q+RM
are in use, is the electricity consumption higher then one 24port (for example
CRS326-24G-2S+RM)?
Other relevant considerations comparing 2* 24 port switch or one 48 port switch
that I might overlook?
Thank you in advance for shining light on this matter.
Of course when you have two switches and they have to be on the same network you should also consider some way to join them, e.g. a DAC cable between two SFP+ ports.
When you compare models, of course you should also consider features like the PoE capability, L3 HW Accel capability, etc. Depending on your needs.
There will be some difference in power usage between a port not in use and a port being used, but it will be minor. Of course PoE provided power is directly reflected in the power consumption.
To continue about PoE: power adapters have generally worse efficiency when running at fraction of rated power and PoE switch with its potentially high power requirement (for maximum PoE consumption) will consume quite more power when (almost) idle than a non-PoE variant.
If you have two switches, then you can use them in MLAG manner to offer high availability to some of connected devices. If using single switch, then you can use a LAG which offers HA of physical connections between device and switch, but doesn’t cover failure of a switch itself … MLAG does.
Drawback of using two switches is the interconnection … which after all has a limited capacity (e.g. 10Gbps) and if the traffic between nodes exceeds this limit, some traffic will get slower. Whether this will be a real problem or not depends on how much traffic will devices generate, but if you spread the twenty 1Gbps devices evenly over two switches, it’s not likely that the interconnect will be a bottleneck. If all gigabit ports get used, then you can add another 10Gbps interconnect and configure both links in LAG … with some luck (and help from statistics) this will offer double capacity of inter-switch link.
When using single switch, they usually come with capacity of wirespeed switching on all ports simultaneously, so slow down doesn’t happen (not for this reason at least).
I am very sorry for my specification:
I actually meant the non-PoE version: [CRS354-48G-4S+2Q+RM].
I corrected the title.
(I already have the PoE switch: CRS354-48P-4S+2Q+RM)
I am comparing: 2 * [CRS326-24G-2S+RM] vs [CRS354-48G-4S+2Q+RM]
Regarding interconnection:
The CRS354-48G also has (2 x 40G QSFP+) like my existing PoE version: CRS354-48P.
The CRS326-24G is lacking the 40G QSFP, so that is a huge con.
It is difficult to give advice especially remote. Both solutions have advantages and disadvantages.
When you have two devices and a fault occurs, you can likely work around it by plugging some cables.
And maybe you can leave one switch off for a while until you need the extra ports.
One device of course is always easier to maintain.
Can you say…“Single Point of Failure”? One 48 port switch working at 50% or less would be very expensive to replace not to mention the downtime in getting a new one setup and configured. I believe that the two 24 port switches would be preferable in your case.
They are cheap enough so that you could in effect acquire a third switch for hot replacement if necessary. This would be so much more expandable if needed. The 10GB SFP+ ports can be setup in Aggregation for communication on your network. They do work extremely efficient in this way. You will not notice delays of any significate value of your communications when connected properly.
I hope this comment gives you some more insight into your question.