Is there or was there reason for us to have all the servers in our domain setup as backup browser servers?
This appears to be the default setting at install.
From Microsoft TechNet
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Number of Browsers in a Domain
Computer Browser service uses the following rules to set the number of browsers in a domain:
• If there is currently a primary domain controller (PDC) in the domain, it is designated as the domain master browse server.
• Every backup domain controller (BDC) in the domain is a backup browse server for the domain. The only exception to this rule occurs when the PDC has failed. In that case, the BDC becomes the domain master browse server.
Note
• PDC failure can be a problem because the DOMAIN[1B] entry, used to locate the Domain Master browse server, is only updated if the backup domain controller is promoted.
If the registry of a computer has the value of the MaintainServerList entry set to Yes, the computer is a backup browse server for the domain or IP subnet.
If no backup browse servers are selected for the domain based on the preceding rules, the master browse server sets the number of backup browse servers to be used for the domain, and then selects — from among those computers that have the value of the MaintainServerList entry set to Auto — that number of specific computers to act as browsers.The table below shows the number of backup browse servers that are selected, based on the number of computers in the domain.
Number of Master or Backup Browse Servers in a Domain
Number of Computers* Number of Backup Browse Servers Number of Master Browse Servers
1 0 1
2 to 31 1 1
32 to 63 2 1
* For each additional 32 computers added to a domain, another backup browse server is added.
In a TCP/IP network, each subnet independently enforces the preceding rules.
This appears to be the default setting at install.
From Microsoft TechNet
------------------------------------------------
Number of Browsers in a Domain
Computer Browser service uses the following rules to set the number of browsers in a domain:
• If there is currently a primary domain controller (PDC) in the domain, it is designated as the domain master browse server.
• Every backup domain controller (BDC) in the domain is a backup browse server for the domain. The only exception to this rule occurs when the PDC has failed. In that case, the BDC becomes the domain master browse server.
Note
• PDC failure can be a problem because the DOMAIN[1B] entry, used to locate the Domain Master browse server, is only updated if the backup domain controller is promoted.
If the registry of a computer has the value of the MaintainServerList entry set to Yes, the computer is a backup browse server for the domain or IP subnet.
If no backup browse servers are selected for the domain based on the preceding rules, the master browse server sets the number of backup browse servers to be used for the domain, and then selects — from among those computers that have the value of the MaintainServerList entry set to Auto — that number of specific computers to act as browsers.The table below shows the number of backup browse servers that are selected, based on the number of computers in the domain.
Number of Master or Backup Browse Servers in a Domain
Number of Computers* Number of Backup Browse Servers Number of Master Browse Servers
1 0 1
2 to 31 1 1
32 to 63 2 1
* For each additional 32 computers added to a domain, another backup browse server is added.
In a TCP/IP network, each subnet independently enforces the preceding rules.