This chapter describes the prerequisites of PrivX deployment.

System Requirements

This section describes the system requirements and specifications for PrivX-system components.

Mandatory Components

A PrivX deployment must include at least one PrivX server for running PrivX services.

Table 2.1. PrivX-Server Requirements and Specifications

Server

System Configuration

4 GB RAM, 2-core CPU, and 15 GB storage for < 10k users

8 GB RAM, 8-core CPU, and 100 GB storage for < 100k users

Supported architecture

x86-64

Supported operating systems

Red Hat Enterprise Linux 7.4 or later 7.x, 8.x (x86-64)

CentOS 7.4 or later 7.x, 8.x (x86-64)

Supported databases

Local or external PostgreSQL and Redis

Network Connectivity

Internet connectivity required

  • For installing dependant libraries during installation and upgrades

  • For PrivX-license activation and verification:

Default network ports in use

Web UI: Port 443 in
Client-certificate authentication: 8443 in
SSH sessions: Port 22 out
SSH Bastion: Port 2222 in
RDP sessions: Port 3389 out
RDP Bastion: Port 3389 in
Email notifications: Port 25, 465, or 587 out
CRL lists for RDP connections: Port 80 in
DNS: Port 53 out
External PostgreSQL: Port 5432 out
External Redis: Port 6379 out
NTP: 123 out

Target-host Authentication

Supported OpenSSH versions

Certificate-based authentication - OpenSSH 6.9 or later, see the section called “Enabling Certificate-Based Authentication for SSH Connections”

Other authentication methods - OpenSSH 5.6 or later

Supported platforms for Windows Domain Controller and Certificate Authority Server

Windows Server 2012 R2, 2016, 2019 (with the latest service packs and updates)

Client Experience

Supported browsers

Latest versions of:

  • Firefox

  • Chrome

  • Safari

  • Edge

System Security

HSM support

SafeNet Network HSM:

  • SafeNet Network HSM

  • Amazon Cloud HSM

  • SoftHSM2

  • nCipher HSM

  • Thales Vormetric

  • Generic pkcs11 provider


Note

Other applications and users with access to PrivX hosts can gain potentially sensitive information from unprotected system memory. For best security we strongly recommend running PrivX on dedicated hosts.

Optional Components

This section describes the system requirements and specifications for optional PrivX components:

  • PrivX Extender

  • PrivX Carrier

  • PrivX Web Proxy

PrivX Extenders proxy connections to target hosts. They are needed for connecting to hosts not directly accessible from PrivX servers.

Table 2.2. PrivX-Extender Requirements and Specifications

Extender

System Configuration

4 GB RAM, 2-core CPU, and 15 GB storage

Supported operating systems

Red Hat Enterprise Linux 7.4 or later 7.x, 8.x (x86-64)

CentOS 7.4 or later 7.x, 8.x (x86-64)

Network Connectivity

Internet connectivity required

For installing dependant libraries during installation and upgrades

Default network ports in use

PrivX connection: Port 443 out
SSH sessions to hosts: Port 22 out
DNS: Port 53 out
RDP sessions to hosts: Port 3389 out
Host-deployment listener: Port 8443 in

PrivX Carriers provide web functionality. Needed if you want to connect to HTTP/HTTPS targets via PrivX.

Table 2.3. PrivX-Carrier Requirements and Specifications

Carrier

System Configuration

64 GB RAM, 16-core CPU, and 100 GB storage for < 50 concurrent web connections

Supported operating systems

Red Hat Enterprise Linux 7.4 or later 7.x, 8.x (x86-64)

CentOS 7.4 or later 7.x, 8.x (x86-64)

Network Connectivity

Internet connectivity required

For installing dependant libraries during installation and upgrades

Default network ports in use

PrivX connection: Port 443 out
Web-proxy connection: Ports 18080, 18443, and 18444 out

Similar to carriers, PrivX Web Proxies also provide web functionality. Needed if you want to connect to HTTP/HTTPS targets via PrivX.

Table 2.4. PrivX-Web-Proxy Requirements and Specifications

Web Proxy

System Configuration

4 GB RAM, 2-core CPU, and 15 GB storage for < 50 concurrent web connections

Supported operating systems

Red Hat Enterprise Linux 7.4 or later 7.x, 8.x (x86-64)

CentOS 7.4 or later 7.x, 8.x (x86-64)

Network Connectivity

Internet connectivity required

For installing dependant libraries during installation and upgrades

Default network ports in use

Carrier connection: Ports 18080, 18443, and 18444 in
Target-host connections: Port 80 and 443 out
PrivX connection: Port 443 out

Supported login methods for autofill

Multi-part form
JSON
XML

Note

For security purposes we recommend setting up all PrivX components on separate, dedicated hosts.

Expected System Performance

A PrivX server that satisfies or exceeds the production requirements is expected to support:

  • 100 000 PrivX users total, with 700 concurrent users.

  • 25 000 target hosts total, with:

    • Up to 1000 hosts added/deployed concurrently.

    • 20 000 target hosts scanned in 2 minutes.

  • Up to 200 concurrent RDP connections for performing typical user operations. Graphically intensive sessions (including video streaming) may reduce the number of supported concurrent connections.

Note

The PrivX microservice architecture supports multiprocessing and benefits from using multiple CPUs or multiple CPU cores.

Reserve enough space for the log data generated by PrivX. Also monitor the log-data growth periodically. In large deployments, PrivX may generate a considerable amount of log data over time. You may configure the PrivX machine to write its log data to an external logging server.

Features Dependent on License

The enabled features and limitations can be viewed on the Settings → License page.

The maximum amount of concurrent SSH, RDP, and HTTPS connections depends on the type of PrivX license. Connections exceeding the maximum allowed connections are disconnected.

The standard PrivX license gives you all the PrivX features except the ones listed below:

  • PrivX Extender: For more information, see the section called “Proxying Connections to Hosts”.

  • Application restrictions through RDP connections: For more information, see the section called “Restricting Users' Access to Applications in RDP Connections”.

  • RDP-native-client connections: For more information, see the section called “RDP Connections with Native Clients”.

For more information about managing your PrivX license, see the section called “PrivX License Management”.

Database Requirements

For production environments we strongly recommend using an external database in your PrivX deployment.

  • Set up a PostgreSQL-database instance and a Redis-server instance. We recommend you employ dedicated instances for PrivX.

    The PostgreSQL superuser (typically postgres) must have a valid password: During initial setup PrivX requires superuser permissions, for creating a PrivX database and a PrivX database user.

    Access to the Redis server may be password-protected.

  • PrivX servers require access to the PostgreSQL database and the Redis server.

    For example with PostgreSQL on Unix, you will need to edit the pg_hba.conf, and insert entries similar to the following:

    hostssl all all <privx_server_ip> md5
  • Connections to the external PostgreSQL database must be SSL-protected:

    • Enable SSL mode in your PostgreSQL configuration (ssl = true).

    • The PostgreSQL server must be configured with a server certificate where the SubjectAltName specifies the DNS and IP address(es) of the server.

    PrivX servers should also be configured to trust the PostgreSQL-server certificate: On each PrivX server, add the PostgreSQL-server CA chain to the system trust anchors. For more information about adding trust anchors to PrivX servers, see the section called “Secure-Connection Setup”.

NTP Clock Synchronization

Machines for PrivX servers must have access to a NTP service for synchronizing system clocks. We recommend using the same NTP service in your whole network.

Due to the just-in-time nature of the certificates issued by PrivX, clock skews greater than a few minutes may cause authorizations to fail.

High-Availability Installation Requirements

For HA deployments, set up a load balancer to distribute connections to PrivX servers. Your load balancer must satisfy the following requirements

  • Each PrivX session must be handled by one PrivX server; for example the load balancer could be configured to use sticky sessions.

  • If you need client-certificate authentication, or SSH/RDP-Bastion connectivity, the load balancer must support TCP-level load balancing.

  • If you need VPC and/or HTTP/HTTPS-connection support, the load balancer must allow PrivX Extenders and/or Carriers to connect to all available PrivX servers. This can be done, for example, by routing Extender/Carrier connections using the round robin algorithm.

Table 2.5. Load-balancer routing requirements

Traffic type

Default port on PrivX

Load-balancing level

Load-balancing method

HTTP user sessions

80

HTTP

sticky

HTTPS user sessions

443

HTTP

sticky

Extender/Carrier Connections

443

HTTP

round robin

HTTPS client-certificate authentication

8443

TCP

any

SSH Bastion

2222

TCP

hash

RDP Bastion

3389

TCP

hash


For an example load-balancer configurations on Nginx that satisfies the requirements, see ???.

HSM Integration

For added security, the PrivX can be integrated with a Hardware Security Module (HSM). This allows storing cryptographic keys on HSM, and encrypting database/filesystem keys using a secret from HSM.

PrivX integrates to HSM providers using PKCS #11. For more information about setting up PrivX with HSM, see the Advanced Deployment articles from https://help.ssh.com/

Note

Decide whether to use HSM before setting up PrivX. HSM support cannot be changed in existing PrivX deployments.

Keys Stored in HSM

The following types of keys may be stored in HSM.

Asymmetric keys

  • CA for issuing just-in-time certificates when users connect using certificate authentication.

  • CA for signing server certificates.

Symmetric keys

  • Master key for encoding/decoding session recordings.

  • Session-authentication keys.

  • Keys for encrypting user and role data.

To store the default CA keys in HSM, your HSM must support the following key-pair-generation mechanisms:

Table 2.6. Required key-generation mechanisms for HSM storage

Key Type

Mechanisms

CA keys

CKM_RSA_PKCS_KEY_PAIR_GEN
CKM_RSA_PKCS

Symmetric keys

CKM_GENERIC_SECRET_KEY_GEN
CKM_SHA_1_HMAC
CKM_SHA*_HMAC (256/384/512)
CKM_AES_KEY_GEN
CKM_AES_GCM

Keys not supported by the HSM are stored in the PrivX database/filesystem, but encrypted using the PKCS #11 instance secret located on the HSM.

Database/Filesystem Keys Encrypted by HSM Integration

Authentication-signing secrets and passphrases are stored in the PrivX database/filesystem. However when HSM integration is enabled, such keys are encrypted using the PKCS #11 instance secret located on the HSM.

GDPR Compliance

Please note that as a PrivX handles user data, that data will be classified as personal information, or Personally Identifiable Information. You must ensure your GDPR compliance and inform your users of handling of their data.

Supported SSH Algorithms

KEX algorithms

  • curve25519-sha256@libssh.org

  • diffie-hellman-group14-sha1

  • ecdh-sha2-nistp256

  • ecdh-sha2-nistp384

  • ecdh-sha2-nistp521

Hostkey algorithms

  • ecdsa-sha2-nistp256

  • ecdsa-sha2-nistp256-cert-v01@openssh.com

  • ecdsa-sha2-nistp384

  • ecdsa-sha2-nistp384-cert-v01@openssh.com

  • ecdsa-sha2-nistp521

  • ecdsa-sha2-nistp521-cert-v01@openssh.com

  • ssh-ed25519

  • ssh-ed25519-cert-v01@openssh.com

  • ssh-dsa

  • ssh-dss-cert-v01@openssh.com

  • ssh-rsa

  • ssh-rsa-cert-v01@openssh.com

Ciphers

  • aes128-ctr

  • aes128-gcm@openssh.com

  • aes192-ctr

  • aes256-ctr

  • chacha20-poly1305@openssh.com

MACs

  • hmac-sha1

  • hmac-sha1-96

  • hmac-sha2-256

  • hmac-sha2-256-etm@openssh.com

Product Limitations

  • Key-combinations using keys unavailable to UK or US keyboards (such as CTRL+ ) do not work on Edge browsers.

  • You cannot transfer folders through file transfer.

  • Ctrl+W key-combination closes the open tab on Firefox.

  • With RDP and Web connections, the clipboard size is limited to 256 KB.

  • PrivX Agent does not work on RHEL 8 with OpenSSH 7.8p1 due to errors on the OpenSSH side.