/dev/fd/13: error in chunked encoding

[Ohadbasan]

Hi

trying to use oz-install throws the following exception: Traceback (most recent call last): File "/bin/oz-install", line 159, in customize or generate_icicle) File "/usr/lib/python2.7/site-packages/oz/RedHat.py", line 706, in generate_install_media customize_or_icicle) File "/usr/lib/python2.7/site-packages/oz/Guest.py", line 1803, in _iso_generate_install_media self._copy_iso() File "/usr/lib/python2.7/site-packages/oz/Guest.py", line 1483, in _copy_iso gfs.tar_out("/", "/dev/fd/%d" % wr) File "/usr/lib/python2.7/site-packages/guestfs.py", line 3708, in tar_out r = libguestfsmod.tar_out (self._o, directory, tarfile, compress, numericowner, excludes) RuntimeError: /dev/fd/13: error in chunked encoding

strace shows the last file opened with fd=13 was: open("/var/lib/rpm/Basenames", O_RDONLY) = 13 , but it was closed close(13) I don't know why it tries to open fd13 later... I think that this is what fails it open("/dev/fd/13", O_WRONLY|O_CREAT|O_NOCTTY|O_TRUNC|O_CLOEXEC, 0666) = 16

the oz version that I am using is oz-0.11.0-2.fc19.noarch

cmd is oz-install -d3 -c oz.cfg appliance.tdl template is

conf [paths] output_dir = /var/lib/libvirt/images data_dir = /var/lib/oz screenshot_dir = .

[libvirt] uri = qemu:///system type = kvm bridge_name = virbr0 cpus = 2 memory = 4048 image_type = raw

[cache] original_media = yes modified_media = no jeos = no

[icicle] safe_generation = no

thank you!

[clalancette]

Hm, that is an odd one that I haven't seen before. It looks like it is squarely in the realm of libguestfs. Unfortunately I have no idea. I'll try to contact the maintainer of libguestfs and get him to comment here.

[rwmjones]

When libguestfs sends files over the link between the appliance and the library (such as when running the guestfs_tar_out call), it sends 8 KByte chunks of data. If the library cannot read a chunk, it will print this error. The normal case would be that system call (eg read(2)) would fail. This is likely to be a "should never happen" issue, and this code is well tested.

Oz calls guestfs_tar_out with the /dev/fd/NN parameter (there's nothing wrong with that). This explains why /dev/fd/NN is shown in the error message.

The bug suggests that strace shows a problem with a file descriptor being closed, but without the complete strace output, plus the precise version of libguestfs, this is not useful.

I can't really debug this further without knowing the precise version of libguestfs, the full strace output, and ideally having a reproducible bug report.

[Ohadbasan]

Hello Thanks for the answer libguestfs is libguestfs-1.22.7-1.fc19.x86_64 I uploaded the strace output to my google drive https://docs.google.com/file/d/0B3eNkDsPQKn5ZDdlNlI3Y0NUOEU/edit

thanks,

Ohad

[rwmjones]

I can't see the full error message because strace truncates strings, but the appliance kernel prints several worrying errors towards the end:

$ fgrep 'read(12,' strace.out 
read(12, "[  174.783567] attempt to access"..., 8192) = 105
read(12, "835\r\ntar: ./repodata/495d3964f86"..., 8192) = 147
read(12, ": Input/output error\r\n", 8192) = 22
read(12, "[  174.823543] attempt to access"..., 8192) = 110
read(12, "[  174.830558] attempt to access"..., 8192) = 195
read(12, "lists.sqlite.bz2: Read error at "..., 8192) = 86
read(12, "[  174.916106] attempt to access"..., 8192) = 132
read(12, " to access beyond end of device\r"..., 8192) = 88
read(12, "tar: ./repodata/5af8199bd0ffb441"..., 8192) = 156
read(12, "error\r\n", 8192)             = 7
read(12, "[  174.974255] attempt to access"..., 8192) = 165
read(12, "[  174.976748] sda: rw=0, want=8"..., 8192) = 222
read(12, "[  175.060976] attempt to access"..., 8192) = 94
read(12, " limit=5720835\r\n", 8192)    = 16
read(12, "[  175.063317] attempt to access"..., 8192) = 105
read(12, "835\r\ntar: ./repodata/b4e0b9342ef"..., 8192) = 153
read(12, ": Input/output error\r\n", 8192) = 22
read(12, "[  175.087326] attempt to access"..., 8192) = 107
read(12, "5\r\n[  175.088603] attempt to acc"..., 8192) = 100
read(12, "mit=5720835\r\ntar: ./repodata/ca5"..., 8192) = 158
read(12, "bytes: Input/output error\r\n[  17"..., 8192) = 64
read(12, "nd end of device\r\n[  175.097439]"..., 8192) = 99
read(12, "access beyond end of device\r\n[  "..., 8192) = 105
read(12, "2ef36b0cde54ee0521fae90b98911db0"..., 8192) = 146
read(12, "[  175.144098] attempt to access"..., 8192) = 85
read(12, "=8230664, limit=5720835\r\n[  175."..., 8192) = 102
read(12, "=0, want=8230664, limit=5720835\r"..., 8192) = 127
read(12, "\r\n[  175.148084] attempt to acce"..., 8192) = 103
read(12, "5720835\r\n", 8192)           = 9
read(12, "[  175.149393] attempt to access"..., 8192) = 105
read(12, "835\r\ntar: ./repodata/TRANS.TBL: "..., 8192) = 100
read(12, "tar: Exiting with failure status"..., 8192) = 73

I'd say your ISO file is corrupted or truncated.

[Ohadbasan]

you were right. I redownloaded the iso and now a dsk image is being created successfully. I have to ask, is there any mailing list or irc channel for oz? I have some question about using the tool thanks!

[clalancette]

There isn't really a mailing list or IRC channel; I just don't have time to hang out on IRC, and there hasn't been enough volume to warrant a mailing list. If you have usage questions, feel free to either email me directly (my email address is clalancette@gmail.com), or open issues on this forum with user questions. I'll answer them as best I can.

For this particular issue, I'm going to close it out. Thanks everyone!