Requirements#

Each Node must satisfy the Hardware Requirements and Software Requirements below, while on the contrary, Firewall Ports must be opened only on the Node that hosts the corresponding service. For example, port 6071 (secure access to the Admin Panel) must be opened only on the Node featuring the Carbonio Admin Panel.

Hardware Requirements#

For each node, these are the hardware requirements to comply with. The Disk Space mentioned in the table refers only to the Operating System and not the data (e-mail quota and e-mail traffic, number of documents stored, and so on), because space requirements for the data may vary considerably.

Moreover, you must take into account the following:

The Node that hosts Carbonio Storage and therefore the emails, is the node requiring more disk space.
The Carbonio Files service requires 4GB of RAM to start, so make sure that the node hosting it has at least 6GB of RAM
The Video Recording feature requires additional storage, which is difficult to estimate in advance. Indeed, it depends on a number of factors, including: Number of participants and number of webcam active during the recording; length and dimension of the recording, screen sharing of the recording, and so on. As a general rule, a 1 hour recording at 1280x720 with 25 frames per second would occupy around 400MB of disk space in webm format.

Purely as an example, if you give a quota of 5GB to each of the 150 users, you need to assign 780GB of disk space (30GB for the OS and at 750 for user’s total quota) to the node.

Software Requirements#

Carbonio is available for 64-bit CPUs only and can be installed on top of any of these vanilla distributions:

Ubuntu 20.04 LTS Server Edition
Ubuntu 22.04 LTS Server Edition
RHEL 8 (see specific requirements)

Support for other distributions will be announced in due course when it becomes available.

The following requirements must be satisfied before attempting to install Carbonio.

The whole Carbonio infrastructure must have at least one public IP address. You need to create a DNS A record that resolves to the public IP (e.g., A mail.example.com)
Hint

You can check a domain’s A record using the CLI utility host:
```
# host -t A example.com
```
To allow the mail server to receive mail, it will be necessary to set up an MX record, which must correspond to the A record (e.g. MX: example.com = mail.example.com )
Hint

You can check a domain’s MX record using the CLI utility host:
```
# host -t MX example.com
```
If either of the A or MX records is not correctly configured, the installation will be temporarily suspended to allow the change of the hostname.
Each Node must be able to carry out DNS resolution autonomously and be able to resolve all other Nodes
For improved security of sending emails, you should also define TXT records for SPF, DKIM and DMARC
Python 3, latest version available on the Operating System chosen
Perl, latest version available on the Operating System chosen
IPv6 must be disabled. Make also sure that the /etc/hosts does not contain any IPv6 entries.

RHEL Specific Requirements#

You need to satisfy these requirements for RHEL.

RHEL 8#

Repositories

If you plan to install Carbonio on RHEL 8, you need an active subscription to the following repositories, i.e., you must be able to fetch packages from them

BaseOS and the other main repositories:

# subscription-manager repos --enable=rhel-8-for-x86_64-baseos-rpms

Appstream:

# subscription-manager repos --enable=rhel-8-for-x86_64-appstream-rpms

CodeReady:

# subscription-manager repos --enable codeready-builder-for-rhel-8-x86_64-rpms

SELinux

SELinux Must be set to disabled or permissive in file /etc/selinux/config. You can check the current profile using the command

# sestatus

Additional Requirements#

Acquaintance with the use of CLI is necessary. All carbonio commands must be executed as the zextras user (these commands will feature a zextras$ prompt), while all other commands must be issued as the root user, unless stated otherwise.

Note

The zextras user is created during the Carbonio installation process, it is not necessary to create it beforehand.
Give meaningful names to the nodes. For example, call them proxy.example.com, mta.example.com, and so on. Replace example.com with your domain name.
During the installation procedure, you will have to write down some configuration options and their value, because they will be needed in the setup of the next nodes. These information are summarised at the end of each node’s installation: copy them to a safe place and keep them at hand until the end of the installation. Example of values include: the IP address (public or private) of a node or the password of a database user.
Depending on the Roles installed on each Node, you need to open in your firewall the ports listed in Firewall Ports for all the services you will offer. In case there are problems in the internal network communication, try to disable the firewall and try again: if it works, there was probably some firewall rule preventing communication.
If none of the nodes is exposed to the Internet, you need to forward two ports from the public IP: port 25/smtp to the Node featuring the MTA Role to be able to receive mail, and port 443/https to the node installing the Proxy Role to allow users to access their webmail from a remote location
If you plan to enable other protocols (e.g., POP, IMAP) you should forward also these ports accordingly. You can refer to section Firewall Ports for a list. Do not open these ports if you do not need these protocols!
Also, for security reasons, port 6071, to access the Carbonio Admin Panel should never be exposed on the Internet, but reachable only from a VPN tunnel or similar mechanisms
The same applies for SSH access to the Nodes: it should only be enabled from internal/management networks, while any remote access must be done via VPN tunnel or equivalent mechanism
The hostname of each Node must be a FQDN.
Every Node must be able to resolve all other host names

Firewall Ports#

Carbonio employs SSL/TLS for the communication, and to operate properly, it is necessary to allow network communication on specific ports.

The Nodes should be able to communicate with the other Nodes through a dedicated network. The ports listed in the Internal Connections must be forwarded on all nodes, while those in the External Connections should be forwarded only on the node on which the corresponding Role is installed. For example, port 443 should be forwarded only on the node hosting the Proxy Role.

Furthermore, ports in Internal and External connections are grouped according to the Role that require them, so all ports listed in a table must be forwarded only on the Node on which the Role is installed.

TCP External Connections#

These ports must be forwarded to allow communication with the Internet.

MTA Role

Port	Protocol	Service
25	TCP	Postfix incoming mail
465	TCP	Message Submission over TLS protocol
587	TCP	Port for SMTP autenthicated relay, requires STARTTLS (or opportunistic SSL/TLS)

Warning

These ports should be exposed only if really needed, and preferably only accessible from a VPN tunnel, if possible, to reduce the attack surface.

Proxy Role

Port	Service
80	TCP	unsecured connection to the Carbonio web client
110	TCP	external POP3 services
143	TCP	external IMAP services
443	TCP	secure connection to the Carbonio web client
993	TCP	external IMAP secure access
995	TCP	external POP3 secure access
6071	TCP	secure access to the Admin Panel
8636	TCP	access to LDAP address books
5222	TCP	XMMP protocol

Warning

The IMAP, POP3, and 6071 ports should be exposed only if really needed, and preferably only accessible from a VPN tunnel, if possible, to reduce the attack surface.

Carbonio VideoServer Role

Port	Protocol	Service
20000-40000	UDP	Client connections for the audio and video streams

TCP Internal Connections#

These ports must be forwarded to allow the Nodes to communicate properly and be able to access Carbonio’s internal services.

Every Node

Port	Service
22	TCP	SSH access
8301	TCP and UDP	management of Gossip protocol [2] in the LAN
9100	TCP	Carbonio Monitoring Node exporter
9256	TCP	Carbonio Monitoring Process exporter

Postgres Role

Port	Protocol	Service
5432	TCP	Postgres access
9187	TCP	Postgres data export to Carbonio Monitoring

Directory Server Role

Port	Protocol	Service
389	TCP	unsecure LDAP connection
636	TCP	secure LDAP connection
9330	TCP	LDAP data export to Carbonio Monitoring

MTA Role

Port	Protocol	Service
25	TCP	Postfix incoming mail
465	TCP	Message Submission over TLS protocol
587	TCP	Port for SMTP autenthicated relay, requires STARTTLS (or opportunistic SSL/TLS)
7026	TCP	bind address of the Milter service

Mailstore & Provisioning (AppServer)

Port	Protocol	Service
7025	TCP	local mail exchange using the LMTP protocol
7071	TCP	Port for SOAP services communication
7072	TCP	NGINX discovery and authentication
7073	TCP	SASL discovery and authentication
7110	TCP	internal POP3 services
7143	TCP	internal IMAP services
7993	TCP	internal IMAP secure access
7995	TCP	internal POP3 secure access
8080	TCP	internal HTTP services access
8443	TCP	internal HTTPS services
8735	TCP	Internal mailbox mailbox communication
8742	TCP	internal HTTP services, advanced module
8743	TCP	internal HTTPS services, advanced module

Carbonio VideoServer Role

Port	Protocol	Service
8188	TCP	Internal connection
8090	TCP	Servlet communication

Proxy Role

Port	Protocol	Service
9113	TCP	nginx data export to Carbonio Monitoring
11211	TCP	memcached access

Carbonio Mesh Role

Port	Protocol	Service
8300	TCP	management of incoming requests from other agents
8302	TCP and UDP	management of Gossip protocol [4] in the WAN
9107	TCP	Carbonio Mesh data export to Carbonio Monitoring
21000-21255	TCP	range for registrations ports for sidecar services (automatically assigned)

Requirements

Contents

Requirements#

Hardware Requirements#

Software Requirements#

RHEL Specific Requirements#

RHEL 8#

Additional Requirements#

Firewall Ports#

TCP External Connections#

TCP Internal Connections#