I temporarily switched our servers to the source package version of
isc-dhcp-server (4.4.2) and the same issue doesn't happens, so I assume
this is a problem with the Debian version of the package.
The servers are now running on Debian 11 without issues (the only
problematic package in the transition from debian 10 to debian 11 was
isc-dhcp-server).
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__________________________
Andrea Turbiglio
Università degli Studi dell’Insubria
Centro Sistemi Informativi e Comunicazione
Servizio Telecomunicazioni - Gestione Rete Dati di Ateneo
Via Valleggio, 11
22100 - COMO
tel. +39 031 238 9784
fax +39 031 238 9709
web www.uninsubria.it
mail andrea.turbig...@uninsubria.it
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