Purchasing and planning network equipment for a company from scratch?

Question

Computer networks

Good day!
I'm sorry for the stupid questions, but I want to hear competent advice.
The situation is this - there is a small organization (18 machines, 2 network printers), which is located on the network facilities of another organization and the question arose of purchasing and transferring to its own server, which already exists (HP Proliant D360 gen9).
I had no experience with this, but after some thought and searching, I came up with an approximate list of the necessary:
​​1. Rack or cabinet 19'', with a depth of at least 800 (and most likely 1000) mm
2. Mikrotik-type managed router for 24 ports
3 Patch panel
4. UPS for 2 KvA, most likely rack
5. Possibly PBX (I have not discussed this yet)
The infrastructure is available - a network, stretched cables, sockets in the offices.
And now, dear connoisseurs, attention to the question - what have I lost sight of, due to my inexperience, and what should I pay attention to? Thanks a lot.

Answer 1

1. For the rack, provide vertical cable managers, horizontal ones will also do.
   
2. Look towards modular patch panels. Killing the usual ones when they are already in operation is still a pleasure.
   
3. As for the PBX, it's really better to look at IP-ATS right away, for example, something from Yeastar.
   
4. Take two UPS at once. One server power supply in UPS1, the second in UPS2. Reservation + simplification of maintenance. If there are funds, then it is better to have an on-line UPS, the issue of voltage stabilization will be automatically resolved, since you have problems.
   
5. Map out the network, keep a cable log, and label everything you can.
   

Answer 2

Gateway, firewall (can be combined in one piece of hardware / virtual machine).
Well, and most importantly, you missed the logical / network diagram in order to imagine what equipment you will need to implement the proposed TK. If there is a detailed technical specification and schemes, many, many more different equipment can grow :)

Answer 3

I would do this:
Router, to connect to the Internet. A pair of switches for redundancy and load balancing. If necessary, wi-fi access points.
PBX must be selected - IP-telephony or analog PBX. IP-telephony can use existing cables, at the same time as LAN. For analog, you will have to allocate separate ones.

Answer 4

This is physics. ISO / OSI 1. Physics is well chosen, though it’s better to take a microtic like RB2011 and a managed switch for 48 ports to it, phones will need to be in a separate VLAN. But physics is not all - now you need to paint the ISO / OSI 2 logic - the Ethernet switching level and the ISO / OSI 3 logic - the level of logical networks. I would venture to suggest that Mikrotik is for connecting to the provider, on the server is the host of the virtualization, are all computers in the switch?

Answer 5

> And now, dear experts, the attention is the question - what have I lost sight of, due to my inexperience, and what should I pay attention to? Thanks a lot.

You need a router and a switch, I already wrote about this in the comments above.
Automatic telephone exchange if you will consider, then ip. True, it will be necessary to buy an ip phone or fence a garden with gateways or analog boards. I can recommend a software implementation that is easy to learn https://www.askozia.ru/
+ you need a server or NAS for backups. Buy either a ready-made solution like synology/qnap , on any suitable machine from https://www.nas4free.org/ or use win+acronis/paragon etc.
The rest must be looked at based on the structure of L1.
Try to draw a network diagram in Visio and I think you will no longer have many questions at once.
Moreover, I would single out a separate machine for monitoring. It can be implemented on the same mikrotik using the simplest monitoring of the dude.