## 11.3.5 Assigning addresses to the HMC and SE 

An HMC can have the following IP configurations: 

GLYPH<SM590000> Statically assigned IPv4 or statically assigned IPv6 addresses 

GLYPH<SM590000> Dynamic Host Configuration Protocol (DHCP)-assigned IPv4 or DHCP-assigned IPv6 addressees 

GLYPH<SM590000> Auto-configured IPv6: 

– Link-local is assigned to every network interface. 

– Router-advertised, which is broadcast from  the router, can be combined with a Media Access Control (MAC) address to create a unique address. 

– Privacy extensions can be enabled for these addresses as a way to avoid the use of the MAC address as part of the address to ensure uniqueness. 

An SE can have the following IP addresses: 

GLYPH<SM590000> Statically assigned IPv4 or statically assigned IPv6 

GLYPH<SM590000> Auto-configured IPv6 as link-local or router-advertised 

IP addresses on the SE cannot be dynamically assigned through DHCP to ensure repeatable address assignments. Privacy extensions are not used. 

The HMC uses IPv4 and IPv6 multicasting$^{2}$ to discover automatically SEs. The HMC Network Diagnostic Information task can be used to identify the IP addresses (IPv4 and IPv6) that are being used by the HMC to communicate to the CPC SEs. 

IPv6 addresses are easily identified. A fully qualified IPV6 address features 16 bytes. It is written as eight 16-bit hexadecimal blocks that are separated by colons, as shown in the following example: 

2001:0db8:0000:0000:0202:b3ff:fe1e:8329 

Because many IPv6 addresses are not fully qualified, shorthand notation can be used. In shorthand notation, the leading zeros can be omitted, and a series of consecutive zeros can be replaced with a double colon. The address in the previous example also can be written in the following manner: 

2001:db8::202:b3ff:fe1e:8329 

If an IPv6 address is assigned to the HMC for remote operations that use a web browser, browse to it by specifying that address. The address must be surrounded with square brackets in the browser’s address field, as shown in the following example: 

## 11.3.6 HMC Multi-factor authentication 

https://[fdab:1b89:fc07:1:201:6cff:fe72:ba7c] 

The use of link-local addresses must be supported by your browser. 

Multi-factor authentication is an optional feature, which is configured on per-user, per-template basis. It enhances security of the z14 models by requiring not only what you know, which is first factor, but also what you have available, which means that only person who owns a specific phone number can log in. 

