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Diary of a Cloud Backup – Part 2: Memopal Reliability

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Day 22 – 22.8Gb uploaded

1.04 Gb/day

After doing so well for a few days the memopal upload ran into a few outages again today.  Lost the service between 14:30 and 20:30 a full six hours.  This time I was around and I had no issues between me an memopal.  The problem is their end.  Once the service resumed, I started seeing a few files upload with a long period before the checks were complete and it moved on to the next file. Another rejection before it kicked in at full speed again.  You can see the issue in the Draytek router traffic log.  The yellow line is the uplink speed.  It will be interesting to see how the faster ADSL service is going to change things.  Its possible that I will still be seeing outages sometimes.

Uplink graph

Uplink graph showing issue

Day 23 – 26Gb uploaded

1.13 Gb/day

Had a fairly decent run of uploads very stable over the past few days.  Tomorrow the ADSL will be switched over so I am turning off the backup until I have the line switched over.

Day 25 – 31.5Gb uploaded – BE excellent, Memopal needs more work

1.26 Gb/day overall.  5.5Gb/day over ADSL+2

It was fantastically easy to setup the DrayTek Vigor 2820.  This was made even easier because BE have a strong community wiki as this entry on routers shows.  I have not tried to optimise the service as yet.  BE support a variety of changes including the line profile volume in Db, and interleaving V fastpath.  I will use the default for now and get Down 8797.34 Kbps, Up 991.83 Kbps.  Not bad for an old line 1.3Km from the exchange but probably with some effort from BT to replace the line through to my faceplate things would be better.  The day before the switch I was getting this on normal ADSL: Down 5891kbps, Up 237.32kbps.  I may experiment later but not until this backup is finished.  The main thing is that the line is consistently faster and reliable.

Memopal backup reliability issues

My backup problems seem to be with memopal itself.  Every now and then the service seems to break down.  After switching to the new ADSL service and kicking off the backup at around midnight on the 24th it ran smoothly for 6 hours.  Then the service broke down again.  A few files did get through.  If I was getting a full 0.9mbps as suggested by the speed test I should be able to upload 10.7Gb in a day.  The way memopal works, a file is uploaded then there is a short pause while some processing is done followed by the next starting.  So even with no outage you would not get the full throughput.  The main thing that is slowing things down though is the outages.  Its been down 8 hours so far today and its still not working properly.  Memopal support usually get back to me by the following day and shortly afterwards things start going again.  Sometimes this happens on its own.  The fact remains though the outages are pretty awful.  I would love it if someone from memopal could comment here and give us all a full technical explanation as its still conceivable that something else is going on.  I suspect though its an issue either with the backup software or the service at the other end.  I base this on the errors I get in the log.  For instance here are a selection:

Memopal error problem with HTTPS Certificate

25/03/2010 14:08:58 – Thread=4236:     Warning: probelm with HTTPS Certificate
5/03/2010 14:09:19 – Thread=4236:     Sending error report to server: errorCode=doyouhaveit network TrustFailure errorData= – Http error (7) [Error establishing connection]

Memopal error Send segment failed with response

25/03/2010 16:09:53 – Thread=4236: Sending error report to server: errorCode=sendfile resp errorData= Send segment failed with response: resp=-2
File checksum: AD7E120C05376DA88E9E042F33EFC4F838C9644B
Segment: 39
Seg. Checksum: 1F7D9C176551EC126F3CDF23F19E4BA2ECCCD8D7
Seg. Size: 524288
Recomputed file checksum: AD7E120C05376DA88E9E042F33EFC4F838C9644B
Recomputer seg. checksum: 1F7D9C176551EC126F3CDF23F19E4BA2ECCCD8D7
File. Size: 23975003

So it seems that memopal still have some work to do even if its just explaining what is actualy causing this to its more technical customers.

Another useful metric / speed test

I found another handy speed test site www.speedtest.net.  This one has an interesting slant as they allow you to measure your speed from home to another location.  In addition a ping test is performed which does not make much difference to my backup but would effect gaming over a connection.  This means I can compare a short hop with the trip to the memopal server in Italy, Rome.  Here are the resulting tests.  As you can see there is very little difference apart from the ping test.  Interesting though.

Speed test London

Speed Test London - Home

SpeedTest London - Rome

Speed Test London - Rome

What next?

Well I have around 50Gb more to upload, so I will post up further pages when more information becomes available. I will also try and solicit a response from memopal as I for one am very interested in working with them to get this service working properly. Even though I have had a few issues its the way forward.

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Published at DZone with permission of Martin Harris, DZone MVB. See the original article here.

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