memojo Posted August 23, 2003 Report Share Posted August 23, 2003 I'm using 5.1 on an iMac 800 running OS 10.2.6 to duplicate to a new 200 GB external FireWire drive. Duplication and verification of about 7 GB from the iMac ran smoothly, at about 380 MB per minute and took only minutes. But duplication of only 2.7 MB on a networked client eMac to the same FireWire drive is running at no more than 20 MB per minute and as slow as 2 to 4 MB per minute. The process started 6 HOURS AGO AND IS STILL RUNNING, WITH HALF A GIG LEFT TO VERIFY!!! Is this normal? Is there anything I can do to speed up performance (short of swapping the FW disk to each of the client computers when I want to run a backup)? Link to comment Share on other sites More sharing options...
CallMeDave Posted August 23, 2003 Report Share Posted August 23, 2003 Quote: duplication of only 2.7 MB on a networked client eMac to the same FireWire drive is running at no more than 20 MB per minute and as slow as 2 to 4 MB per minute. - What OS is the eMac running? - What sort of network connection is there between the Client and the Retrospect machine? - If you bypass all other network hardware (hubs, switches, punch-down, etc) and use a single, known-good ethernet cable between them (with appropriate network settings) what sort of speeds do you see? Dave Link to comment Share on other sites More sharing options...
memojo Posted August 24, 2003 Author Report Share Posted August 24, 2003 Quote: - What OS is the eMac running? - What sort of network connection is there between the Client and the Retrospect machine? - If you bypass all other network hardware (hubs, switches, punch-down, etc) and use a single, known-good ethernet cable between them (with appropriate network settings) what sort of speeds do you see? - 10.2.6 - Two clients [eMac and an iBook] are connected to a hub via ethernet. That hub is connected to another hub, to which a cable modem and the Retrospect iMac are connected: iMac (Retrospect)/FW drive | hub – cable modem | hub – iBook | eMac - Bypassing the hubs isn't an option because of the logistics involved. Link to comment Share on other sites More sharing options...
CallMeDave Posted August 24, 2003 Report Share Posted August 24, 2003 Quote: Bypassing the hubs isn't an option because of the logistics involved. Knowing if (that?) your networking infrastructure is the cause of your slow communications would be helpful to your troubleshooting. - Are they hubs, or switches? What speed are they (10BaseT or 10/100BaseT)? What make/model? - What exactly are the logistics in play here, and might they be relevant? The eMac is a reasonably movable single box, that _could_ be hand carried to another room for testing. - Can you take the second hub out of the chain and connect the eMac directly to a port on the first hub? - Does the iBook demonstrate faster networking speeds? - If so, can you swap ports/cables between the iBook and the eMac? Dave Link to comment Share on other sites More sharing options...
memojo Posted August 24, 2003 Author Report Share Posted August 24, 2003 Quote: Knowing if (that?) your networking infrastructure is the cause of your slow communications would be helpful to your troubleshooting. - Are they hubs, or switches? What speed are they (10BaseT or 10/100BaseT)? What make/model? - What exactly are the logistics in play here, and might they be relevant? The eMac is a reasonably movable single box, that _could_ be hand carried to another room for testing. - Can you take the second hub out of the chain and connect the eMac directly to a port on the first hub? - Does the iBook demonstrate faster networking speeds? - If so, can you swap ports/cables between the iBook and the eMac? All possibilities that occured to me after your initial reply got me thinking. I'll probably experiment when I get the opportunity. The hubs, BTW, are Farallon Streamline Starlet 5-port 10BaseT left over from before all our machines were 100BaseT compatible. Can I expect much/any performance boost by upgrading to 100BaseT? And is my understanding correct that subsequent Duplicate/Replace Entire Drive sessions will back up only files that are new or have changed, and won't replace the entire contents of the FW drive each time, so at least the overall time required for the process should be shorter, if not the MB/minute speed? Thanks. Link to comment Share on other sites More sharing options...
mcswgn Posted August 24, 2003 Report Share Posted August 24, 2003 Quote: memojo said: All possibilities that occured to me after your initial reply got me thinking. I'll probably experiment when I get the opportunity. The hubs, BTW, are Farallon Streamline Starlet 5-port 10BaseT left over from before all our machines were 100BaseT compatible. Can I expect much/any performance boost by upgrading to 100BaseT? Maybe. The wiring needs to support it--you need Cat 5 or better on all cable and hardware, and certain installation standards need to be met. (E.g., minimum bend radius.) Trying to use 100base-T on low quality cabling can actually *reduce* speed due to lost packets and timeout issues. This does, however, have the feel of a networking problem. A 10Mb/sec network only translates to a theoretical maximum of about 60MB/min assuming no other traffic (including any responses from server to client). In reality, if you see upwards of 40MB/min you are doing pretty good on a 10base-T network. Below 10MB/min, though, is pretty slow unless you know there is a lot of other traffic. I would encourage you to explore the sorts of things CallMeDave was suggesting. Look at the speed to each client and see if there is a difference. If there is no difference, walk the iBook to the server and either connect directly with a cross-over cable (you would need to assign fixed IP numbers to the two since they wouldn't get any numbers from the cable modem) or at least to the hub that has the cable modem, and disconnect the "downstream" hub, to eliminate as much as of your network as possible. If you still see very slow speeds try swapping the two hubs to see if one of the hubs is bad. If you decide to look at new equipment, I would suggest the small 10/100 switches. However, you need to be careful. An auto sensing device will only know whether the device at the other end supports the higher speeds, because they tell each other so, not that the cable can support it. If both sides agree on the higher speed and the wiring can't handle it, your throughput will go right through the floor. In other words, if you aren't sure, only buy from a store that has a "100% satisfaction guaranteed or your money back" Quote: And is my understanding correct that subsequent Duplicate/Replace Entire Drive sessions will back up only files that are new or have changed, and won't replace the entire contents of the FW drive each time, so at least the overall time required for the process should be shorter, if not the MB/minute speed? Correct. Retrospect won't recopy something that is already there (if it's exactly the same). Link to comment Share on other sites More sharing options...
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