You would do something like this
<form>
  <label>New_dashboard</label>
  <fieldset submitButton="false">
    <input type="dropdown" token="clients">
       <label>dropdown1(clients)</label>
      <search>
        <query>index=whatever host=client*|stats count by host</query>
        <earliest>-60m@m</earliest>
        <latest>now</latest>
      </search>
      <fieldForLabel>host</fieldForLabel>
      <fieldForValue>host</fieldForValue>
      <prefix>host="</prefix>
      <suffix>"</suffix>
    </input>
    <input type="dropdown" token="servers">
       <label>dropdown1(clients)</label>
      <search>
        <query>index=whatever host=server*|stats count by host</query>
        <earliest>-60m@m</earliest>
        <latest>now</latest>
      </search>
      <fieldForLabel>host</fieldForLabel>
      <fieldForValue>host</fieldForValue>
      <prefix>host="</prefix>
      <suffix>"</suffix>
    </input>
  </fieldset>
   <!-- The Rest of your Dashboard goes here -->
</form>
This will produce two tokens, the value of which would be "host=clientxxx" or "host=serverxxx"
Hi
It could be usefull if you create before a lookup file to create the list and save theses searches to run every night.
index=xxx host=cliente* |table host |outputlookup clients.csv <- ALL TIME
index=xxx host=server* |table host | outputlookup servers.csv <- ALL TIME
You would do something like this
<form>
  <label>New_dashboard</label>
  <fieldset submitButton="false">
    <input type="dropdown" token="clients">
       <label>dropdown1(clients)</label>
      <search>
        <query>index=whatever host=client*|stats count by host</query>
        <earliest>-60m@m</earliest>
        <latest>now</latest>
      </search>
      <fieldForLabel>host</fieldForLabel>
      <fieldForValue>host</fieldForValue>
      <prefix>host="</prefix>
      <suffix>"</suffix>
    </input>
    <input type="dropdown" token="servers">
       <label>dropdown1(clients)</label>
      <search>
        <query>index=whatever host=server*|stats count by host</query>
        <earliest>-60m@m</earliest>
        <latest>now</latest>
      </search>
      <fieldForLabel>host</fieldForLabel>
      <fieldForValue>host</fieldForValue>
      <prefix>host="</prefix>
      <suffix>"</suffix>
    </input>
  </fieldset>
   <!-- The Rest of your Dashboard goes here -->
</form>
This will produce two tokens, the value of which would be "host=clientxxx" or "host=serverxxx"
Thanks alot rsennett. This worked.