msweet at apple.com
Tue Dec 20 07:28:17 PST 2016
CUPS doesn't do anything special for the resolver - sounds like a glibc regression. > On Dec 20, 2016, at 7:48 AM, Zdenek Dohnal <zdohnal at redhat.com> wrote: > > Hi, > > I encountered this issue on Fedora 25 with CUPS-2.2.0, but it worked on > RHEL 7 with CUPS-1.6.3. I have stopped and disabled Network Manager, > network is controlled by systemd-networkd (enabled+started), > systemd-resolved (enabled+started) is in charge of DNS. My configuration > is this: > > $ cat /etc/systemd/network/ens9.network > [Match] > Name=ens9 > > [Network] > IPForward=no > Address=fd3b:d910:cd43::3/64 > $ > > $ cat /etc/systemd/system/systemd-networkd.service.d/local.conf > [Service] > ExecStartPre=-/sbin/ip link set eth0 down > ExecStartPre=-/sbin/ip addr flush dev eth0 > Restart=on-failure > $ > > $ cat /etc/cups/cupsd.conf > MaxLogSize 0 > LogLevel warn > Listen localhost:631 > Listen /var/run/cups/cups.sock > Listen [fd3b:d910:cd43::3]:631 > Browsing Off > DefaultShared no > WebInterface Yes > DefaultEncryption Never > HostNameLookups on > <Location /> > Order allow,deny > Allow from all > </Location> > <Policy default> > <Limit All> > Allow from All > </Limit> > </Policy> > $ > > $ cat /etc/systemd/system/cups.service.d/local.conf > [Service] > ExecStartPre=/bin/sleep 2 > LimitCORE=1073741824 > $ > > $ cat /etc/systemd/network/wired.network > [Match] > Name=eth0 > > [Network] > IPForward=no > DHCP=ipv4 > > [DHCP] > UseHostname=true > SendHostname=true > $ > > And I created symlink /etc/resolv.conf, which is pointed to > /run/systemd/resolve/resolv.conf: > > $ ln -sf /run/systemd/resolve/resolv.conf /etc/resolv.conf > > File /etc/resolv.conf contains: > > nameserver 192.168.122.1 > > Then when I opened CUPS web interface and ran strace on cupsd process, I > saw correct IP of nameserver in strace output: > > connect(6, {sa_family=AF_INET, sin_port=htons(53), > sin_addr=inet_addr("192.168.122.1")}, 16) = 0 > recvfrom(6, > "\0019\205\200\0\1\0\1\0\0\0\0\16dnsmasq_server\0\0\1\0\1\300\f\0\1\0\1\0\0\0\0\0\4\300\250z\27", > 1024, 0, {sa_family=AF_INET, sin_port=htons(53), > sin_addr=inet_addr("192.168.122.1")}, [16]) = 48 > > , but when I changed nameserver in /etc/resolv.conf to, for example, > 8.8.8.8, CUPS still worked with old nameserver until CUPS is restarted. > This behavior works with CUPS-1.6.3, so was there any changes regarding > using /etc/resolv.conf by CUPS? Or it is regression? Thank you in advance. > > Best regards, > > Zdenek > > > _______________________________________________ > cups-devel mailing list > cups-devel at cups.org > https://lists.cups.org/mailman/listinfo/cups-devel _________________________________________________________ Michael Sweet, Senior Printing System Engineer