Alert Type

PSN - Product Support Notification
Low/NotificationLow risk
Low/NotificationNo service impact.

Product Affected

PTX-Series

Alert Description

Copying the JUNOS image via FTP/SFTP on PTX devices using WAN ports takes more time than management ports. A WAN port is a port on the line card - having the prefix "et-". The management port is either the re0:mgmt-0.0/re1:mgmt-0.0 or em0.

Copying a new JUNOS image to some of the PTX devices via WAN ports can take up to 1 hour.
This issue can be seen on PTX running either JUNOS or JUNOS Evolved software.

The main reason for this delay is the limited bandwidth for control protocol packets between RE and FPC. Queue size on PTX platforms has limited bandwidth which is shared between various control protocols. 

We are making improvements  in :
  • JUNOS 21.4 and later.
  • JUNOS EVOLVED  21.4R2-EVO and later.

Note: increasing the "ddos-protection" setting for particular protocols does not improve the copying time of the image to RE via an interface of FPC. 
 

Solution

The delay can be reduced if we use management port (em0 or re0:mgmt-0/re1:mgmt-0.0) instead of wan port to copy images.

We currently recommend  to either use management port (em0 or re0:mgmt-0/re1:mgmt-0.0) instead of wan port  Or schedule for longer window if WAN ports have to be used for copying the JUNOS image to the PTX routers. 
 

Modification History

First publication 2022-05-27