Limits

Overview of ccloud³ limits: network restrictions, SMTP rules, VM limits, IP limits and known technical limitations.

Restrictions

Certain types of network traffic on ccloud³ VMs are restricted to prevent malicious actions such as reflected DDoS attacks. These restrictions also prevent features such as the configuration of Direct Server Return and the use of ccloud³ VMs as routers and site-to-site VPN gateways. Future changes to our network will support this functionality. Until then, some workarounds involve the use of a VPN mesh network or an overlay network.

The following types of traffic are restricted:

• Incoming TCP and UDP traffic on port 11211 from external networks (due to the Memcached amplification attacks in March 2018).

• Multicast traffic.

• Traffic that does not match the IP address or MAC address of a ccloud³ VM.

• SMTP via reserved IP addresses and IPv6.

All ccloud³ VMs have a network throughput limit of 1 Gbps.

You cannot create more than 10 ccloud³ VMs at the same time via the Control Panel or the API.

SMTP port 25 is blocked for all new accounts on ccloud³ VMs. As an alternative, we recommend using a dedicated email delivery platform and generally advise against running your own mail server.

You select the underlying processor architecture (AMD or Intel) when creating the VM within your pool.

Root password resets are not available for operating systems with internally managed passwords, including Fedora.

ccloud³ VMs cannot be assigned more than one reserved IP address at a time.

Known issues

Due to our network design, traceroute diagnostics between ccloud³ VMs may show 100% packet loss during the last two hops. This packet loss is to be expected and does not affect connectivity between ccloud³ VMs.