Hostname

class rmote.tools.hostname.Hostname

Bases: Tool

Manage system hostname and /etc/hosts entries. Requires root for mutating operations.

Change the hostname in a disposable container with its own UTS namespace:

>>> from rmote.tools import FileSystem
>>> remote = getfixture("debian_tool")
>>> remote(Hostname.set, "rmote-example")
True
>>> remote(Hostname.set, "rmote-example")
False
>>> remote(Hostname.get)
'rmote-example'
>>> remote(FileSystem.read_str, "/etc/hostname").strip()
'rmote-example'
>>> remote(Hostname.hosts_entry, "192.0.2.1", "web")
True
>>> remote(Hostname.hosts_entry, "192.0.2.1", "web")
False

static get()

Return the current running hostname.

Reads from /proc/sys/kernel/hostname which always reflects the live kernel value regardless of what /etc/hostname contains.

Return type:

Text

Returns:

The hostname string.

static hosts_entry(ip, *names)

Ensure /etc/hosts has an entry mapping ip to names.

If a line for ip already exists with exactly the same hostnames (in the same order), this is a no-op. If it exists with different hostnames, the line is replaced in-place. If no line exists for ip, one is appended.

Comment lines and blank lines are left untouched.

Parameters:

• ip (Text) – The IP address for the entry (IPv4 or IPv6).

• *names (Text) – One or more hostnames to associate with ip.

Return type:

bool

Returns:

True if /etc/hosts was modified.

Raises:

ValueError – If no names are provided.

static set(name)

Set the system hostname idempotently.

Applies the change immediately by writing to /proc/sys/kernel/hostname and persists it to /etc/hostname. No external commands are required.

Parameters:

name (Text) – The desired hostname.

Return type:

bool

Returns:

True if the hostname was changed, False if it was already set to name.