We are getting many notifications of "attempted a failed login using an invalid username "admin"". This is happening to 3 of the 15 sites that we manage. We have reduced the login attempts to 5 and blocked IP addresses for 2 months. We have also blocked several ranges of IP address and several browser matches. So far there has been no real improvement as shortly afterwords we receive attempts from other IP addresses.
Question - Other than being a pain in the *** is this like to cause any issues? Our username is never "admin" and our passwords are 10 to 12 randomly selected characters.
Thanks in advance.