Talvez um pouco presunçoso da minha parte simplesmente postar o arquivo de ajuda, mas, em suma, é a resposta que você procura.
Além disso, consulte dcdiag.exe para obter outras informações sobre o DNS, pois a replicação depende muito de sua infraestrutura de DNS estar totalmente operacional.
C:\repadmin.exe /?
Usage: repadmin <cmd> <args> [/u:{domain\user}] [/pw:{password|*}]
[/retry[:<retries>][:<delay>]]
[/csv]
Use these commands to see the help:
/? Displays a list of commands available for use in repadmin and their
description.
/help Same as /?
/?:<cmd> Displays the list of possible arguments <args>, appropriate
syntaxes and examples for the specified command <cmd>.
/help:<cmd> Same as /?:<cmd>
/experthelp Displays a list of commands for use by advanced users only.
/listhelp Displays the variations of syntax available for the DSA_NAME,
DSA_LIST, NCNAME and OBJ_LIST strings.
/oldhelp Displays a list of deprecated commands that still work but
are no longer supported by Microsoft.
Supported <cmd> commands (use /?<cmd> for detailed help):
/kcc Forces the KCC on targeted domain controller(s) to immediately
recalculate its inbound replication topology.
/prp This command allows an admin to view or modify the
password replication policy for RODCs.
/queue Displays inbound replication requests that the DC needs to issue
to become consistent with its source replication partners.
/replicate Triggers the immediate replication of the specified directory
partition to the destination domain controller from the source DC.
/replsingleobj Replicates a single object between any two domain
controllers that have common directory partitions.
/replsummary The replsummary operation quickly and concisely summarizes
the replication state and relative health of a forest.
/rodcpwdrepl Triggers replication of passwords for the specified user(s)
from the source (Hub DC) to one or more Read Only DC's.
/showattr Displays the attributes of an object.
/showobjmeta Displays the replication metadata for a specified object
stored in Active Directory, such as attribute ID, version
number, originating and local Update Sequence Number (USN), and
originating server's GUID and Date and Time stamp.
/showrepl Displays the replication status when specified domain controller
last attempted to inbound replicate Active Directory partitions.
/showutdvec displays the highest committed Update Sequence Number (USN)
that the targeted DC's copy of Active Directory shows as
committed for itself and its transitive partners.
/syncall Synchronizes a specified domain controller with all replication
partners.
Supported additional parameters:
/u: Specifies the domain and user name separated by a backslash
{domain\user} that has permissions to perform operations in
Active Directory. UPN logons not supported.
/pw: Specifies the password for the user name entered with the /u
parameter.
/retry This parameter will cause repadmin to repeat its attempt to bind
to the target dc should the first attempt fail with one of the
following error status:
1722 / 0x6ba : "The RPC Server is unavailable"
1753 / 0x6d9 : "There are no more endpoints available from the
endpoint mapper"
/csv Used with /showrepl to output results in comma separated
value format. See /csvhelp
Note: Most commands take their parameters in the order of "Destination or
Target DSA_LIST", then a "Source DSA_NAME" if required, and finally the
NC or Object DN if required.
<DSA_NAME> (or <DSA_LIST>) is a Directory Service Agent binding
string. For Active Directory Domain Services, this is simply a network
label (such as a DNS, NetBios, or IP address) of a Domain Controller.
For Active Directory Lightweight Directory Services, this must be a
network label of the AD LDS server followed by a colon and the LDAP
port of the AD LDS instance
Examples (AD DS): dc-01
dc-01.microsoft.com
Examples (AD LDS): ad-am-01:2000
ad-am-01.microsoft.com:2000
<Naming Context> is the Distinguished Name of the root of the NC
Example: DC=My-Domain,DC=Microsoft,DC=Com
Note: Text (Naming Context names, server names, etc) with International or
Unicode characters will only display correctly if appropriate fonts and
language support are loaded.