shair@ux1.cso.uiuc.edu (Bob Shair) (06/13/91)
henkel%nepjt@ncsuvx.ncsu.edu (Chuck Henkel) writes: >Context: Two RS/6000 Model 320s running 3001. > Tape drive configured for 512 byte blocks, no ECC >I'm trying to use rdump to back up a filesystem on "rs1" to a >cartridge tape on "rs2": >rdump -0 -c -f rs2:/dev/rmt0.4 /u >only writes about 10 meg on the tape, then asks for another. If I use >a high density tape, (3M 6150, /dev/rmt0), it only puts about 20 meg >on the tape, then asks for another. >The "-b" flag (blocksize) has no apparent effect. Backing up >filesystems on rs2 (the machine with the tape) works fine. >What's the deal? The deal is we accidentally omitted the -d (density) and -s (size) flags from the man pages for rdump when we shipped AIX 3.1; they're in updated versions. For a DC600A 120MB tape (rmt0.4) specify -s 9000 -d 1250 I append the appropriate Flags from 3.1.5 manual. rdump Command Syntax rdump [ -b Number1 ] [ -c] [ -d Number2 ] [ -l Number3 ] [-s Number4 ] [ -u] [ -w] [ -W] [ -Level] -f Machine:Device [ FileSystem] Flags -b Number1 Specifies the number of blocks to write in a single output operation. If you do not specify the Number1 parameter, the rdump command uses a default value appropriate for the physi- cal device selected. Larger values of the Number1 parameter, result in larger physical transfers to tape devices. -c Specifies that the tape is cartridge, not nine-track. -d Number2 Specifies the density of the tape in bits per inch (BPI). This value is used in calculating the amount of tape used per volume. If you do not specify a value for the Number2 parameter, the rdump command uses a default density of 1600 BPI. For a default density of 8000 BPI, specify the -c flag. -l Number3 Uses the Number3 parameter as the limit of the total number of blocks to use on the remote backup medium. -s Number4 Allows you to specify the size of the tape in feet us- ing the Number4 parameter. If you do not specify a tape size, rdump defaults to a tape size of 2300 feet. For a de- fault size of 1700 feet, use the -c flag. When the tape drive reaches the specified size, the rdump command waits for the tape to be changed. -- Bob Shair shair@chgvmic1.vnet.ibm.com Scientific Computing Specialist SHAIR@UIUCVMD (bitnet) IBM Champaign
henkel%nepjt@ncsuvx.ncsu.edu (Chuck Henkel) (06/13/91)
Context: Two RS/6000 Model 320s running 3001. Tape drive configured for 512 byte blocks, no ECC I'm trying to use rdump to back up a filesystem on "rs1" to a cartridge tape on "rs2": rdump -0 -c -f rs2:/dev/rmt0.4 /u only writes about 10 meg on the tape, then asks for another. If I use a high density tape, (3M 6150, /dev/rmt0), it only puts about 20 meg on the tape, then asks for another. The "-b" flag (blocksize) has no apparent effect. Backing up filesystems on rs2 (the machine with the tape) works fine. What's the deal? And, why doesn't this work: backup -0 -b 126 -f - /u | rsh rs2 dd of=/dev/rmt0 obs=126 The dd dies immediately with "invalid argument to system call" or somesuch. In fact, I can't get dd to write on the tape at all. -- | Chuck Henkel | | | Department of Nuclear Engineering | Support nuclear power. | | N.C. State University | | | henkel%nepjt@ncsuvx.ncsu.edu | |
johnson@aixwiz.austin.ibm.com (Fred L. Johnson) (06/13/91)
In article <HENKEL%NEPJT.91Jun12234846@nepjt.ncsuvx.ncsu.edu>, henkel%nepjt@ncsuvx.ncsu.edu (Chuck Henkel) writes: ... > Context: Two RS/6000 Model 320s running 3001. > Tape drive configured for 512 byte blocks, no ECC > ... > And, why doesn't this work: > > backup -0 -b 126 -f - /u | rsh rs2 dd of=/dev/rmt0 obs=126 > > The dd dies immediately with "invalid argument to system call" or > somesuch. In fact, I can't get dd to write on the tape at all. The dd is dying because of the obs=126. This is telling dd to use 126 byte blocks for its write system call. The 1/4" tape only accepts i/o requests in multiples of 512 bytes, hence the EINVAL returned to dd from the write system call. Using 126b would tell dd to use a block size of 126, 512 byte blocks, and this should make the tape device driver happier. - Fred My remarks and opinions are mine alone... ____________________________________________________________________________ | | | | Fred L. Johnson | Internet: johnson@aixwiz.austin.ibm.com | | IBM Personal Systems Programming | inet: johnson@tanstaafl.austin.ibm.com | | AIX BOS Field Quality | vnet: FJOHNSON at AUSVMQ | | 11400 Burnet Road, 994/3401 | phone: (512) 823-4706 | | Austin, TX 78758-3493 | tie line: 793-4706 | |__________________________________|_________________________________________|
mrl@uai.com (Mark R. Ludwig) (06/14/91)
In article <HENKEL%NEPJT.91Jun12234846@nepjt.ncsuvx.ncsu.edu>, henkel%nepjt (Chuck Henkel) writes: >backup -0 -b 126 -f - /u | rsh rs2 dd of=/dev/rmt0 obs=126 > >The dd dies immediately with "invalid argument to system call" or >somesuch. In fact, I can't get dd to write on the tape at all. I *do* hope you mistyped your post and had obs=126b ^ or obs=126k ^ or something more than 126 bytes! On the other hand, I tried this and got: dd: 0511-053 The write failed. : Invalid Argument so maybe you did. In that case, I suggest you try a larger blocksize.$$ -- INET: mrl@uai.com UUCP: uunet!uaisun4!mrl PSTN: +1 213 822 4422 USPS: 7740 West Manchester Boulevard, Suite 208, Playa del Rey, CA 90293 WANT: Succinct, insightful statement to occupy this space. Inquire within.