MINSNRM is the Minimum Noise Margin for both upstream and downstream ADSL communications.
Q: A customer spotted a message in the syslog after restarting the ADSL connection:
“SNR Margin value lower than MINSNRM”.
He asks “Is MINSNRM an attribute of each type of ADSL connection? ie… Does 211011/Std have a fixed setting ? And 211801 another setting ? Or can it be tuned for a specific line ? E.g…my ISP can set STABLE or NORMAL connection at the exchange (or they could for ADSL ?). Is there any way to find what MINSNRM is set to (for Vigor 2820Vn)? Does it change with firmware updates And how does it work? E.g… If SNRM is below MINSNRM for longer than ??? Seconds…then resync the line?”
A: There are upstream and downstream MINSRNM parameter respectively, which are defined and set by the CO profile. The purpose is to retrain the modem when the target SNR margin is below min SNR margin due to the increasing noise or line condition becoming worse. The min SNR margin could affect the reboot criteria. (depending on how you set the reboot criteria). That means Vigor2820/CPE doesn’t have MINSNRM value. The values are defined by Co.