We're thinking about using Slony to replicate from a production server running 
Postgres 8.0 (installed from the Gentoo package) to a read-only server 
running Postgres 8.2 (based on Ubuntu, I'm not sure exactly what version; 
it's actually a VMware virtual appliance).  Based on my reading so far,  
there shouldn't be a big problem with this;  one use-case mentioned in the 
documentation is a minimal-downtime upgrade to a newer server.

However,  I'm running into trouble getting it it work on my test workstation,  
Ubuntu Hardy with an 8.0 instance and an 8.2 instance installed from Ubuntu 
packages (8.0 is from "dapper-backports").  There's a "postgresql-8.3-slony1" 
package containing the "xxid.so" and "slony1_funcs.so", but of course those 
won't work with older servers because of API changes.  I decided to build 
those files only from Slony source.

My first problem was that the "./configure" script was claiming that the 
Postgres version was 8.3, even though the 8.3 server was not currently 
installed.  I ended up editing "config.h" and invoking gcc manually to build 
the two .so files.

The next problem,  on which I'm stuck, seems to be an error in the way SLony 
is referring to a sequence:

<stdin>:7: PGRES_FATAL_ERROR 
select "_davidswaybill".initializeLocalNode(1, 'koios'); 
select "_davidswaybill".enableNode(1);  - ERROR:  function setval("unknown", 
bigint) does not exist
HINT:  No function matches the given name and argument types. You may need to 
add explicit type casts.
CONTEXT:  SQL statement "SELECT  setval('"_davidswaybill".sl_rowid_seq',  
$1 ::int8 * '1000000000000000'::int8)"
PL/pgSQL function "initializelocalnode" line 26 at perform
<stdin>:7: ERROR: no admin conninfo for node 134598976

Has anyone seen this kind of error before?  Any idea how to fix it?


-- 

David L. Lambert
  Software Developer,  Precision Motor Transport Group, LLC
  Work phone 517-349-3011 x215
  Cell phone 586-873-8813