This sets how often the card re-raises an alert for the switching port's Pearl ASIC VBR2 (the second, lower-priority variable-bit-rate service class) queue overflow condition. As the lower-priority variable-bit-rate queue relative to VBR1, this alert firing in isolation, without a corresponding VBR1 alert, tells the admin the overflow risk is concentrated in the card's lower-tier variable-bit-rate traffic rather than its higher-priority equivalent. For example, seeing repeated VBR2-only overflow alerts on a port suggests the lower-priority traffic class is the one running out of queue headroom, not the VBR1 class.