[SRX] What occurs internally during the commit process on Junos devices?

Description

This article provides information about what occurs internally on Junos devices during the commit process.

Solution

Understanding the commit process :

Any changes that are made to the configuration have to be committed, for them to be applied. When a commit command is issued on a Junos platform device, several internal events take place, which the user cannot notice via the CLI. But, to get a glimpse, the display detail CLI knob can be used. This has to be used along with the commit command piping it. For example:

{primary:node0}[edit] root@CL-PRIV-FW1# commit | display detail node0: 2012-06-22 16:21:30 EDT: merging latest committed configuration 2012-06-22 16:21:30 EDT: start loading commit script changes 2012-06-22 16:21:30 EDT: no commit script changes 2012-06-22 16:21:30 EDT: no transient commit script changes 2012-06-22 16:21:30 EDT: finished loading commit script changes 2012-06-22 16:21:30 EDT: copying juniper.db to juniper.data+ 2012-06-22 16:21:30 EDT: finished copying juniper.db to juniper.data+ 2012-06-22 16:21:30 EDT: exporting juniper.conf 2012-06-22 16:21:31 EDT: expanding interface-ranges 2012-06-22 16:21:31 EDT: finished expanding interface-ranges 2012-06-22 16:21:31 EDT: expanding groups 2012-06-22 16:21:31 EDT: finished expanding groups 2012-06-22 16:21:31 EDT: setup foreign files 2012-06-22 16:21:31 EDT: update license counters 2012-06-22 16:21:31 EDT: finish license counters 2012-06-22 16:21:31 EDT: propagating foreign files 2012-06-22 16:21:31 EDT: complete foreign files 2012-06-22 16:21:31 EDT: dropping unchanged foreign files 2012-06-22 16:21:31 EDT: executing 'ffp propagate' 2012-06-22 16:21:31 EDT: daemons checking new configuration 2012-06-22 16:21:31 EDT: Routing protocols process checking new configuration 2012-06-22 16:21:32 EDT: Interface control process checking new configuration 2012-06-22 16:21:32 EDT: Web management gatekeeper process checking new configuration 2012-06-22 16:21:33 EDT: Event processing process checking new configuration 2012-06-22 16:21:33 EDT: Link Layer Discovery Protocol checking new configuration 2012-06-22 16:21:33 EDT: updating shared candidate configuration 2012-06-22 16:21:33 EDT: commit wrapup... 2012-06-22 16:21:33 EDT: start ffp activate 2012-06-22 16:21:33 EDT: executing 'ffp activate' 2012-06-22 16:21:34 EDT: activating '/var/etc/rc.conf.inc' 2012-06-22 16:21:34 EDT: activating '/var/etc/newsyslog.conf' 2012-06-22 16:21:34 EDT: activating '/var/etc/certs' 2012-06-22 16:21:34 EDT: activating '/var/etc/crontab' 2012-06-22 16:21:34 EDT: executing foreign_commands 2012-06-22 16:21:34 EDT: /bin/sh /etc/rc.ui ui_setup_users (sh) 2012-06-22 16:21:34 EDT: executing ui_commit in rc.ui 2012-06-22 16:21:39 EDT: finish ffp activate 2012-06-22 16:21:39 EDT: copying configuration to juniper.save 2012-06-22 16:21:39 EDT: activating '/var/run/db/juniper.data' 2012-06-22 16:21:39 EDT: notifying daemons of new configuration 2012-06-22 16:21:39 EDT: notifying mgd(1) 2012-06-22 16:21:39 EDT: signaling 'Management process', pid 1119, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:39 EDT: notifying rpd(2) 2012-06-22 16:21:39 EDT: signaling 'Routing protocols process', pid 1173, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:39 EDT: notifying dcd(15) 2012-06-22 16:21:39 EDT: signaling 'Interface control process', pid 1201, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:39 EDT: notifying httpd-gk(31) 2012-06-22 16:21:39 EDT: signaling 'Web management gatekeeper process', pid 1189, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:39 EDT: notifying eventd(82) 2012-06-22 16:21:39 EDT: signaling 'Event processing process', pid 890, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:39 EDT: notifying lldpd(89) 2012-06-22 16:21:39 EDT: signaling 'Link Layer Discovery Protocol', pid 17089, signal 1, status 0 with notification errors enabled 2012-06-22 16:21:40 EDT: Rotate backup configs 2012-06-22 16:21:44 EDT: commit complete commit complete

What happens with the configuration files?

When a configuration change is made and committed, the configuration files on the flash are overwritten with the new configuration and they are also rotated for the rollback purpose. A copy of the Active Configuration is created, which is known as Candidate Configuration, when editing the configuration.

Any changes being made are added to the Candidate Configuration, before committing. When the commit is complete, the active configuration is also modified with the same changes.

What daemons are involved?

Daemons are notified of the change, which has been implemented on the device, during the commit process. The new configuration has to be approved by specific daemons, which is known as commit check. They are also notified after the commit. Multiple daemons are notified, depending on the configuration change.

For example, consider the following configuration changes:

Adding a static route :

{primary:node0}[edit]
root@test# show | compare 
[edit routing-options static]
route 0.0.0.0/0 { ... }
+ route 172.0.0.0/8 next-hop 172.22.145.1;

{primary:node0}[edit]
root@CL-PRIV-FW1# commit | display detail 
node0: 
2012-06-22 16:21:30 EDT: merging latest committed configuration
2012-06-22 16:21:30 EDT: start loading commit script changes
2012-06-22 16:21:30 EDT: no commit script changes
2012-06-22 16:21:30 EDT: no transient commit script changes
2012-06-22 16:21:30 EDT: finished loading commit script changes
2012-06-22 16:21:30 EDT: copying juniper.db to juniper.data+
2012-06-22 16:21:30 EDT: finished copying juniper.db to juniper.data+
2012-06-22 16:21:30 EDT: exporting juniper.conf
2012-06-22 16:21:31 EDT: expanding interface-ranges
2012-06-22 16:21:31 EDT: finished expanding interface-ranges
2012-06-22 16:21:31 EDT: expanding groups
2012-06-22 16:21:31 EDT: finished expanding groups
2012-06-22 16:21:31 EDT: setup foreign files
2012-06-22 16:21:31 EDT: update license counters
2012-06-22 16:21:31 EDT: finish license counters
2012-06-22 16:21:31 EDT: propagating foreign files
2012-06-22 16:21:31 EDT: complete foreign files
2012-06-22 16:21:31 EDT: dropping unchanged foreign files
2012-06-22 16:21:31 EDT: executing 'ffp propagate'
2012-06-22 16:21:31 EDT: daemons checking new configuration
2012-06-22 16:21:31 EDT: Routing protocols process checking new configuration
2012-06-22 16:21:32 EDT: Interface control process checking new configuration
2012-06-22 16:21:32 EDT: Web management gatekeeper process checking new configuration
2012-06-22 16:21:33 EDT: Event processing process checking new configuration
2012-06-22 16:21:33 EDT: Link Layer Discovery Protocol checking new configuration
2012-06-22 16:21:33 EDT: updating shared candidate configuration
2012-06-22 16:21:33 EDT: commit wrapup...
2012-06-22 16:21:33 EDT: start ffp activate
2012-06-22 16:21:33 EDT: executing 'ffp activate'
2012-06-22 16:21:34 EDT: activating '/var/etc/rc.conf.inc'
2012-06-22 16:21:34 EDT: activating '/var/etc/newsyslog.conf'
2012-06-22 16:21:34 EDT: activating '/var/etc/certs'
2012-06-22 16:21:34 EDT: activating '/var/etc/crontab'
2012-06-22 16:21:34 EDT: executing foreign_commands
2012-06-22 16:21:34 EDT: /bin/sh /etc/rc.ui ui_setup_users (sh)
2012-06-22 16:21:34 EDT: executing ui_commit in rc.ui
2012-06-22 16:21:39 EDT: finish ffp activate
2012-06-22 16:21:39 EDT: copying configuration to juniper.save
2012-06-22 16:21:39 EDT: activating '/var/run/db/juniper.data'
2012-06-22 16:21:39 EDT: notifying daemons of new configuration
2012-06-22 16:21:39 EDT: notifying mgd(1)
2012-06-22 16:21:39 EDT: signaling 'Management process', pid 1119, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:39 EDT: notifying rpd(2)
2012-06-22 16:21:39 EDT: signaling 'Routing protocols process', pid 1173, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:39 EDT: notifying dcd(15)
2012-06-22 16:21:39 EDT: signaling 'Interface control process', pid 1201, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:39 EDT: notifying httpd-gk(31)
2012-06-22 16:21:39 EDT: signaling 'Web management gatekeeper process', pid 1189, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:39 EDT: notifying eventd(82)
2012-06-22 16:21:39 EDT: signaling 'Event processing process', pid 890, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:39 EDT: notifying lldpd(89)
2012-06-22 16:21:39 EDT: signaling 'Link Layer Discovery Protocol', pid 17089, signal 1, status 0 with notification errors enabled
2012-06-22 16:21:40 EDT: Rotate backup configs
2012-06-22 16:21:44 EDT: commit complete
commit complete

Changing chassis cluster configuration :

When heartbeat-interval and hearbeat-threshold are added to the configuration, the chassisd and JSRPD daemons are notified of the change.

{primary:node0}[edit]
root@test# show | compare 
[edit chassis cluster]
+ heartbeat-interval 1000;
+ heartbeat-threshold 4;

{primary:node0}[edit]
root@test# commit | display detail 
node0: 
2012-06-22 16:36:32 EDT: merging latest committed configuration
2012-06-22 16:36:32 EDT: start loading commit script changes
2012-06-22 16:36:32 EDT: no commit script changes
2012-06-22 16:36:32 EDT: no transient commit script changes
2012-06-22 16:36:32 EDT: finished loading commit script changes
2012-06-22 16:36:32 EDT: copying juniper.db to juniper.data+
2012-06-22 16:36:33 EDT: finished copying juniper.db to juniper.data+
2012-06-22 16:36:33 EDT: exporting juniper.conf
2012-06-22 16:36:33 EDT: expanding interface-ranges
2012-06-22 16:36:33 EDT: finished expanding interface-ranges
2012-06-22 16:36:33 EDT: expanding groups
2012-06-22 16:36:33 EDT: finished expanding groups
2012-06-22 16:36:33 EDT: setup foreign files
2012-06-22 16:36:33 EDT: update license counters
2012-06-22 16:36:33 EDT: finish license counters
2012-06-22 16:36:33 EDT: propagating foreign files
2012-06-22 16:36:33 EDT: complete foreign files
2012-06-22 16:36:33 EDT: dropping unchanged foreign files
2012-06-22 16:36:33 EDT: executing 'ffp propagate'
2012-06-22 16:36:33 EDT: daemons checking new configuration
2012-06-22 16:36:33 EDT: Chassis control process checking new configuration
2012-06-22 16:36:35 EDT: Juniper Stateful Redundancy Protocol Daemon checking new configuration
2012-06-22 16:36:35 EDT: updating shared candidate configuration
2012-06-22 16:36:35 EDT: commit wrapup...
2012-06-22 16:36:35 EDT: start ffp activate
2012-06-22 16:36:35 EDT: executing 'ffp activate'
2012-06-22 16:36:36 EDT: activating '/var/etc/certs'
2012-06-22 16:36:36 EDT: executing foreign_commands
2012-06-22 16:36:36 EDT: /bin/sh /etc/rc.ui ui_setup_users (sh)
2012-06-22 16:36:36 EDT: not executing ui_commit in rc.ui
2012-06-22 16:36:36 EDT: finish ffp activate
2012-06-22 16:36:36 EDT: copying configuration to juniper.save
2012-06-22 16:36:36 EDT: activating '/var/run/db/juniper.data'
2012-06-22 16:36:36 EDT: notifying daemons of new configuration
2012-06-22 16:36:36 EDT: notifying chassisd(5)
2012-06-22 16:36:36 EDT: signaling 'Chassis control process', pid 1116, signal 1, status 0 with notification errors enabled
2012-06-22 16:36:36 EDT: notifying jsrpd(67)
2012-06-22 16:36:36 EDT: signaling 'Juniper Stateful Redundancy Protocol Daemon', pid 1129, signal 1, status 0 with notification errors enabled
2012-06-22 16:36:36 EDT: Rotate backup configs
2012-06-22 16:36:42 EDT: commit complete
commit complete

To notify all the daemons of the configuration change, commit full has to be used.

Modification History

2020-07-23: Article reviewed for accuracy; made minor non-technical edits.