Peter, No problem. You brought up another tid bit to add to the conversation. ;-)
Mark On 02/29/2012 06:17 AM, Peter Homann wrote: > Hi Mark, > > Oops, sorry I misunderstood the conversation. > > Cheers, > > Peter > > On 29/02/2012 10:15 PM, Mark Wendt wrote: > >> Peter, >> >> I was referring to Kirk's not seeing port 1502 after he assigned it in >> the loadusr statement, and how the OS handles ports above 1024. >> >> Mark >> >> On 02/29/2012 06:07 AM, Peter Homann wrote: >> >>> Hi, >>> >>> Port 502 is assigned to Modbus, so that's what slaves should use by default. >>> >>> Cheers, >>> >>> >>> Peter. >>> >>> On 29/02/2012 9:40 PM, Mark Wendt wrote: >>> >>> >>>> On 02/28/2012 05:21 PM, Kirk Wallace wrote: >>>> >>>> >>>>> ... snip >>>>> >>>>> I think I know a little more now. I was able to bring up >>>>> "loadusr classicladder --modslave" (I didn't know the rt component had >>>>> to be loaded too). My netstat returned the same result above with >>>>> "0.0.0.0:9502". I then did a ifconfig to find my network computer's >>>>> addresses with 192.168.1.10 (eth0) and 127.0.0.0 (localhost) being >>>>> listed. I nmap both addresses and found port 9502 open on both, so it >>>>> seems by default, "--modslave" will listen on all addresses (two in this >>>>> case), with "all or any addresses" being called out as "0.0.0.0". >>>>> http://en.wikipedia.org/wiki/0.0.0.0 >>>>> >>>>> If I use "loadusr classicladder --modslave --modbus_port=1502" netstat >>>>> sees port 1502 as listening, nmap doesn't see it whereas it did see 9502 >>>>> previously. My guess is that as any ports above 1000 have lighter >>>>> restrictions, maybe ports above a higher value are handled differently >>>>> too, so 1502 doesn't show where 9502 does. I guess I have more work to >>>>> do. >>>>> >>>>> I haven't tried connecting to the LinuxCNC slave with a master yet. >>>>> >>>>> >>>>> >>>> Actually, ports 1024 and below are considered "privileged" ports. Any >>>> ports above that are considered "non-privileged" ports and are all >>>> treated the same. Do a 'netstat -a | grep 1502' and see if the 1502 >>>> port shows up. >>>> >>>> Mark >>>> ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
