When using slcli to list virtual servers in a Softlayer account:
slcli vm list
it takes a long time and eventually produces the following error:
SoftLayerAPIError(SOAP-ENV:Server): Internal Error
This used to work in the same account. Listing VMs in specific data centers works OK still which makes me think that I'm hitting some built-in limit on the number of objects that can be returned... Is there a limit and if there is what is it?
If there was a limit, I believe you would have seen an error/notification. The request times out when it tries to return a huge amount of records. As mentioned earlier try using the limit switch to limit the number of records or use filters. This article speaks more about filters.