This article discusses how to avoid PIC config violations while inserting the following optics for enabling 400G support on PTX10003:

• QSFP56-DD-400GBASE-DR4  
• QSFP56-DD-400G-FR4 

PTX10003, does not contain any pluggable PICs. They are all built-in.  You can plug-in the optics to the FPCs, and depending on the speed configured on those optics, respective interfaces will be created. On PTX10003, only ports 0, 4, 5, 9 within each logical PIC support 400-Gigabit ethernet mode.

In the example below, port 4 is configured on FPC 0 PIC 0 with 400G speed without specifying any configuration on other ports on that PFE. PIC-config violations error message appears:

labroot@d20-4# show chassis fpc 0 
pic 0 {
    port 4 {
        speed 400g;
    } 
} 

labroot@d20-4# run show chassis pic pic-slot 0 fpc-slot 0 | find Violations     
PIC Config Violations:

  No.    Error-Message
  1      Constraint violated: PFE1 Bandwidth 500G 
  2      port 2 cannot be used when port 4 is 400G 

When using 400G on port 0, the total bandwidth (speed x number-of-subports) of port 1 must be less than 100G and port 2 must be configured as 'unused'. When using port 4 as 400G, port 3 must be configured with total bandwidth of less than 100G and port 2 must be configured 'unused'. That is, when a port is configured in 400-Gigabit ethernet mode, you cannot configure speed of the adjacent port to be more then 100-Gbps, and the middle port (2 between 0~4 or 7 between 5~9) must be set to unused.

In order to resolve PIC config violations, configure port 2 as unused port and port 3 with speed less than 100G. The configuration below is needed for port 2 and 3 in order to use port 4 as 400G connection. Show chassis pic command shows pic-config violations are cleared after committing the changes below.

labroot@d20-4# show chassis fpc 0                  
pic 0 {
    port 2 {
        unused;
    }
    port 3 {
        speed 100g;   
    }
    port 4 {
        speed 400g;
    }
}

labroot@d20-4# run show chassis pic pic-slot 0 fpc-slot 0    
FPC slot 0, PIC slot 0 information:
  Type                             4x400G/10x200G/20x100G
  State                            Online    
  PIC version               255.09
  Uptime                         1 day, 19 hours, 20 minutes, 57 seconds

PIC port information:
                         Fiber                    Xcvr vendor       Wave-    Xcvr         JNPR
  Port Cable type        type  Xcvr vendor        part number       length   Firmware     Rev
  4    400G-FR4          SM    JUNIPER-1W1        740-085349        1301 nm  1.3          REV 01
 5    400GBASE-DR4      SM    JUNIPER-1W1        740-085351        1311 nm  1.3          REV 01

Port speed information:

  Port  PFE      Capable Port Speeds
  0      25      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 1x400G 4x100G 
  1      25      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 
  2      25      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 8x50G 
  3      24      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 
  4      24      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 1x400G 4x100G 
  5      27      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 1x400G 4x100G 
  6      27      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 
  7      27      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 8x50G 
  8      26      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 
  9      26      4x10G 4x25G 8x25G 1x40G 1x100G 2x100G 1x200G 8x50G 1x400G 4x100G