This article provides information about the No child found for aggregate nexthop XXX on ifl XX. Ignoring error message and its significance in the production environment.

Messages, such as the following, are flooding the system syslog file:

(FPC Slot X, PIC Slot 0) SPCX_PIC0 kernel: aggregate nexthop XXXX on ifl XXX. Ignoring...

No child found for aggregate nexthop XXX on ifl XX. Ignoring...

• The message is logged after the ARP learning. When the routing engine kernel learns the ARP entry, it creates a next-hop entry (NH) and sends it to the SPU kernel. In certain scenarios, the NH duplicate message, which is sent to the SPU kernel, arrives later; possibly when there are a lot of ARP entries, interfaces are changing the state, or arp entries have to be re-learned.
• This message was initially logged at the WARNING log level and as it turned out after thorough checking, it is not an indication of a problem; so the severity to was reduced to LOG_DEBUG to have it appear only when debugging is required.
• However, when many of these messages are created at the same time at the SPU kernel level, the ring buffer that keeps the log entries starts getting overwritten and information about log severity is lost. So, these messages are generated in the messages log, even when the maximum logging levels are not enabled.

Such messages do not affect the traffic and no action is required; it can be ignored. As per PR726580 , such messages will be removed from the 11.4R6, 12.1R4, 12.2R2, and 12.3R1 versions.