Cvmfs on a diskless machine with alien cache

Client
1

Hi,

I’m trying to set up a cvmfs client on a set of diskless machines. These machines share a NFS mounted root filesystem based on CentOS 7.

cvmfs client comes from cvmfs-2.9.3-1.2.osg36.el7.x86_64.

The configuration in /etc/cvmfs/default.local is:

CVMFS_REPOSITORIES=oasis.opensciencegrid.org
CVMFS_QUOTA_LIMIT=20000
CVMFS_HTTP_PROXY='http://proxy1.xxx.fr:3128;http://proxy2.xxx.fr:3128'
CVMFS_NFS_SOURCE=no

CVMFS_ALIEN_CACHE=/nfsmounted/cvmfs_cache
CVMFS_QUOTA_LIMIT=-1
CVMFS_SHARED_CACHE=no

I have initialised the cache using:

cvmfs2 __MK_ALIEN_CACHE__ /nfsmounted/cvmfs_cache/ $CVMFS_UID $CVFMS_GID

The cache are is mounted with the following parameters in /etc/fstab:

nfs.server.fr:/vol/vol1/nfsmounted		/nfsmounted	nfs     rw,bg,nfsvers=3		0 0

but cvmfs_config probe fails:

❯ cvmfs_config probe
required configuration repository directory does not exist: /cvmfs/config-osg.opensciencegrid.org/etc/cvmfs
Failed to read CernVM-FS configuration

In the log output, there is this warnings:

Dec 12 08:55:02 xxx.xxx.fr cvmfs2[3318]: (config-osg.opensciencegrid.org) could not acquire workspace lock (9) (9 - cache directory/plugin problem)
Dec 12 08:55:02 xxx.xxx.fr cvmfs2[3293]: required configuration repository directory does not exist: /cvmfs/config-osg.opensciencegrid.org/etc/cvmfs

Any idea on what I doing wrong ?

Thanks.

Emmanuel.

2

By default, the cvmfs client uses the same directory for the cache and for the workspace. The workspace directory is the directory where cvmfs keeps lock files, control files, pipes, sockets etc. This directory must be local (can be on a tmpfs).

In your case, try adding to your configuration CVMFS_WORKSPACE=/path/to/local/dir, e.g. /var/lib/cvmfs.

1 Like
3

Hi Jakob,

Thanks for your reply.

In fact in my case, CVMFS_WORKSPACE was already set to /var/lib/cvmfs. But I thought it needed to be persistent, hence I had a line about it in /etc/statetab, which in the end is a NFS mounted directory.

I have removed this line from statetab, and added a empty /var/lib/cvmfs in /etc/rwtab, which has the effect to bind this directory to tmpfs. It fixed my issue.

Thanks again,

Emmanuel.