douge@risky.Convergent.COM (Douglas Estes) (06/15/91)
A nasty rumor is being spread that the WBAK command is unreliable for full backup of a node using the following command. wbak -f 1 //node_1234. I have used this command for 8 years and had no problem. I was recently told, however, that this has never worked reliably since the beginning of the Apollo Aegis OS existence. I was told, however that the following command would work reliably. wbak -f 1 //node_1234/... for a full node backup. Is there any Apollo expert out there who can verify this statement and relieve of me the uncertainty, that 8 years of archiving are unreliable? Thanks Douglas C. Estes
mike@bellcorebellcore.com (Mike Lukacs 21341) (06/20/91)
In article <5609@risky.Convergent.COM>, douge@risky.Convergent.COM (Douglas Estes) writes: |> A nasty rumor is being spread that the WBAK command is unreliable for |> full backup of a node using the following command. |> wbak -f 1 //node_1234. I have used this command for 8 years and had no |> problem. I was recently told, however, that this has never worked reliably |> since the beginning of the Apollo Aegis OS existence. |> |> I was told, however that the following command would work reliably. |> wbak -f 1 //node_1234/... for a full node backup. |> |> Is there any Apollo expert out there who can verify this statement and |> relieve of me the uncertainty, that 8 years of archiving are unreliable? |> |> Thanks |> Douglas C. Estes In early versions of the Aegis operating system (I think versions 4.x -> 6or7.x) the cpt (copy tree) command was HORRIBLY broken. When the size of the tree exceeded some large threshold (10 MBytes < T < 100 MBytes) the directory table being built by the command overflowed, and the command started to act like a dlt (DELETE tree) command DESTROYING THE DATA THAT YOU WERE ATTEMPTING TO BACK UP!!! This bug persisted through more than one release of the operating system but was definitely fixed by SR 8.0 (several years ago). If you had been bitten by this bug You Would Know It. It happened at WBAK time. However; wbak -f 1 //node_1234 is horribly wastefull in that the system files can not and need not be backet up in this manner. wbak -f 1 //node_1234/local_user makes much more sense. Just make sure to tell your users that anything hidden in funny places will not be backed up. DISCLAIMER: The opinions expressed | M. E. Lukacs NVC-3X-330 in the above are my own, and not | Bell Communications Research(BELLCORE) those of Bell Communications Research. | 331 Newman Springs Road By Law, BELLCORE may not have such | Red Bank, New Jersey, USA 07701-7040 opinions; and if they did, they would | not tell you for free. And I am not | (201)or(908) 758-2876 FAX: 758-0889 the person who would be giving out | official opinions anyway. And unless | mike@nyquist.bellcore.com you can PROVE that this isn't a | "First 'mike' on the UUCP network" forgery, I did not say this. | (ca.1974)