What hardware is needed for a server PC?

Question

Computers

Gentlemen, please tell me what hardware is needed for a server server PC to approximately serve such an infrastructure at the facility:

1) I look towards Proxmox the hypervisor.
2) In the future telephony. 1-2 external telephone numbers, 2-5 internal telephony. I have never encountered telephony, probably it will be necessary to raise whatever Asterisk is.
3) Perhaps a simple mail server in the future.
4) Web server for a simple site.
5) Remote access (ssh, vnc, vpn)
6) Zabbix monitoring of access points, switches, routers, cameras / etc.
7) File cleaner for workers - Samba.
8) Unifi Controller for Ubiquiti access points. And CAMsMAN for Mikotik outlets.
9) Actually Internet access gateway, several dhcp pools, NAT, DNS, Vlan. Fault tolerance/Aggregation of Internet UPlinks from 2-3 providers.

Answer 1

First, you need multiple servers because you can't put all your eggs in one basket.
The rest doesn't make sense.

Answer 2

First, you will need a microtic (well, or a cisco, if you don't have money). Moreover, a microtic is not sickly, if you think about fault tolerance and multilink - this means BGP, and dragging BGP to yourself without fullview is not a particularly meaningful act. Gateway, dhcp, dns, nat, remote access - all this went to Mikrotik One virtual machine
- mail, web (external)
One virtual machine - zabbix, samba
One bare-metal machine for asterisk, Why did I say that bare-metal? To implement the desired set of FXO and FXS. A carrier card is taken, port sub-cards are placed on it, as a rule, ports come in fours (although FXO, which are usually few, can be twos)
You need normal rack-mounted server hardware, you can use it to be able to connect to it via KVM (making tyrnet on Mikrotik will give such an opportunity)
In addition, I would take another shelf for backups - it depends on the degree of autonomy of the object. On ittelo.ru you can buy new and used server hardware at an affordable price.
UPD: When buying a machine for asterisk, be careful - port cards are usually full-length, either a riser or a 4U
case. UPD2: If internal SIP phones, FXS ports are not needed. If external numbers are also via SIP, nothing is needed at all, and then the asterisk can be put into a virtual machine.

Answer 3

Normally you need iron. Load dependent.
Something at the level of Xeon E-3 v5 will be normal.

Answer 4

Server hardware needs redundant hotswap power supplies, a hotswap disk basket, IPMI and other stuffing.

Answer 5

This is not a PC needed, it already pulls on a whole server cabinet.