Re: [libvirt] [PATCH] Default to qemu:///system if accessible

On 03-09-2010 15:59, Daniel Veillard wrote: >> diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c >> index a945710..17e6ead 100644 >> --- a/src/remote/remote_driver.c >> +++ b/src/remote/remote_driver.c >> @@ -1086,7 +1086,7 @@ remoteOpen (virConnectPtr conn, >> if (!conn->uri) { >> DEBUG0("Auto-probe remote URI"); >> #ifndef __sun >> - if (getuid() > 0) { >> + if (access(LIBVIRTD_PRIV_UNIX_SOCKET, W_OK)) { >> DEBUG0("Auto-spawn user daemon instance"); >> rflags |= VIR_DRV_OPEN_REMOTE_USER; >> if (!autostart || > > Hum, that sounds like a change of semantic. Depends. I think of the (getuid() > 0) as a check for whether you can access the privileged UNIX socket that simply doesn't take into account that users other than root may have been given this privilege by way of membership of the group owning the socket. > Before as non root you would span a local daemon, now you use the system > one. I'm not saying it's a bad thing in most cases but it's a serious > change, and we try to avoid those in general. As I suggested in another e-mail a short while ago in this thread, I'm making this change to maintain the status quo in Ubuntu. We already do this in virsh and virt-viewer and something very, very similar in virt-manager. Someone recently dropped the virt-viewer patch by mistake, and I decided to make the change directly in libvirt to not change how libvirt has behaved for us in the past couple of years, so I can certainly relate to your desire to not change the behaviour. Personally, at least, I find this behaviour much more pleasant. On all my servers, I just grant whoever needs to be able to deal with the VM's on it access to the socket (by adding them to the libvirtd group), and that's it. I don't need to instruct them to set per-application environment variables or whatever. Generally, I use libvirt on two classes of machine: Workstations/laptops (where I'm functionally the only user), or on servers whose job is to run virtual machines and nothing else. In the former case, obviously I want to use the systemwide libvirtd to get access to all the fancy networking things. I have absolutely no motivation to use qemu:///session on there anymore.

In the latter case, only people who are supposed to manage the virtual machines will have access to the server, and IMO they have no business running stuff under qemu:///session on that box.