Granting/denying access according auth-method

[dump at gmx.info]

Dear list,

I'm using freeradius 3 almost in standard config with mysql as storing
facility. I have PEAP an EAP active. Usually EAP via TLS or TTLS/PAP is
used, because the passphrases could be stored in SHA-1 encryption. PEAP
is sometimes necessary for me too but it uses MS-CHAPv2 which needs
cleartext-PW. Due to this I would like to restrict authentication vis
MS-CHAPv2 and reactivate it when needed.

I would prefer to do it via the radcheck-table for quickly activating
and deactivate is easily. I read that it's possible via users-file, but
I can't find any useful information/manual to me what to fill into the
radcheck tables.

May somebody have the idea or manual I need to follow/read?

Many thanks in advance and
best regards
Jens