Junos OS with an upgraded FreeBSD kernel provides a clean-slate implementation of Junos OS on top of a pristine (minimally modified) and current version of the FreeBSD OS.
The platforms currently running Junos OS with upgraded FreeBSD
are listed in Table 1.
Table 1: Upgraded FreeBSD Kernel Support by Hardware Platform
Platforms
|
CPU Type
|
Release Introduced
|
|---|---|---|
MX240, MX480, MX960, MX2010, MX2020
|
Intel
|
15.1
|
EX9200
|
Intel
|
15.1
|
QFX5200
|
Intel
|
15.1X53-D30
|
The major processing changes are as follows:
- Interactions between Junos OS and the upgraded FreeBSD kernel use well-established interfaces because Junos OS is now layered on a minimally modified and current version of FreeBSD.
- Symmetric multiprocessing (SMP) is enabled by default.
- FreeBSD provides a consistent runtime environment for all Junos OS platforms.
There are also major changes in file structures and software
packages. These changes are as follows:
- New packages use XML description files instead of scripts.
- Hybrid packages are used to install legacy or replacement build images in the general form junos-upgrade-x.tgz, where x is a variable such as mx-x86-64-15.1-20150114 (the whole package name is junos-upgrade-mx-x86-64-15.1-20150114.tgz).
- Multiple package sets (a collection of installed packages) are stored on the router at the same time. Sets can be either active (the currently used set), pending (the set that should be used at the next reboot), or previous (a formerly active set). Non-recovery snapshots (but not recoverable image snapshots) are available for the package sets to preserve package content lists.
There is now a separate Operations, Administration, and Maintenance
(OAM) volume (
oam) distinct from
the Junos OS volume (junos). This
provides support for downgrades from replacement build images (that
is, those using the upgraded FreeBSD kernel) to the legacy Junos OS
with a different kernel. The OAM volume allows you to recover the
Junos OS volume using recovery snapshots.
One major change is the distinction between recovery snapshots
and non-recovery snapshots.
The major characteristics of the recovery snapshots are
as follows:
- Recovery snapshots are full copies of the packages and configuration taken at the time the snapshot command is issued.
- Recovery snapshots reside on the OAM volume or USB medium.
The major characteristics of the non-recovery snapshots
are as follows:
- Non-recovery snapshots are snapshots residing on the Junos OS volume that refer to the current running set of packages and a copy of the configuration at the time the snapshot command is issued.
- Non-recovery snapshots do not need to copy the whole Junos OS installation and so are very fast.
- Non-recovery snapshots can be requested as the boot image for the next reboot.
The upgraded FreeBSD kernel requires changes to several commands
and statements and their related parameters. The new and changed actions
are summarized in Table 2. For
details on the changes, see the topics covering the specific command
or statement.
Table 2: New and Changed Commands and Statements for Junos OS with Upgraded
FreeBSD
Command or Statement
|
Release Introduced
|
Change
|
|---|---|---|
request system snapshot delete snapshot
|
15.1
|
New action
|
request system snapshot recovery
|
15.1
|
New action
|
request system snapshot load snapshot
|
15.1
|
New action
|
request system recover volume
|
15.1
|
New action: volume is either /junos-volume or /oam-volume
|
request system snapshot
|
15.1
|
Changed action
|
show system snapshot
|
15.1
|
Changed action
|
request system reboot media
|
15.1
|
Changed action with new media options
|
The new FreeBSD kernel also requires that several commands and
statements are now deprecated. In some cases, these commands and statements
generate an error, and, in other cases, the result is appropriate
for the new kernel. The deprecated commands and statements are summarized
in Table 3. For details,
see the topics covering the specific command or statement.
Table 3: Deprecated Commands and Statements for Junos OS with Upgraded
FreeBSD
Deprecated Command or Configuration Statement
|
Release Deprecated
|
|---|---|
| Deprecated Command | |
request system partition abort
|
15.1
|
request system partition compact-flash
|
15.1
|
request system partition hard-disk
|
15.1
|
request system snapshot <config-partition>
|
15.1
|
request system snapshot <root-partition>
|
15.1
|
request system snapshot <slice>
|
15.1
|
request system software delete-backup
|
15.1
|
request system software rollback <force>
|
15.1
|
show system processes providers
|
15.1
|
show system snapshot <slice>
|
15.1
|
| Deprecated Configuration Statement | |
set system mirror-flash-on-disk
|
15.1
|
