Hello Lucas,
Sorry, you can not change it to never expire, the maximum validity period of the SAN password can only be set to 999 days, and cannot be set to 99999 days like Linux, it never expires.
You can set the SAN password policy to not change the FS side password: the number of historical passwords is set to 0, and the password validity period is set to 999. The password is valid for 999 days, which can reduce the number of password changes. The number of historical passwords is 0. The new password can be the same as the old password. There is no need to change the password on the FS.
I hope it is of help!