Working on some MX series routers recently I encountered a problem I’d never seen before, essentially preventing the configuration from being committed:
buraglio@rtr# commit check re0: error: could not open configuration database (juniper.data+)This is a very annoying problem and is terribly inconvenient as you can probably imagine. So, my first instinct is to drop down to the shell and starting hacking at it UNIX style.
buraglio@rtr>start shellFrom there I wanted to see the file system and check out the stats of what it thinks we have.
buraglio@rtr% df -h Filesystem Size Used Avail Capacity Mounted on /dev/ad0s1a 3.5G 313M 2.9G 10% / devfs 1.0K 1.0K 0B 100% /dev /dev/md0 63M 63M 0B 100% /packages/mnt/jbase /dev/md1 53M 53M 0B 100% /packages/mnt/jkernel64-12.3R3.4 buraglio@rtr% 82M 82M 0B 100% /packages/mnt/jpfe-X960-12.3R3.4 /dev/md3 5.0M 5.0M 0B 100% /packages/mnt/jdocs-12.3R3.4 buraglio@rtr% 104M 104M 0B 100% /packages/mnt/jroute-12.3R3.4 buraglio@rtr% clearM 28M 0B 100% /packages/mnt/jcrypto64-12.3R3.4 /dev/md6 38M 38M 0B 100% /packages/mnt/jpfe-common-12.3R3.4 /dev/md7 92K 92K 0B 100% /packages/mnt/jplatform-12.3R3.4 /dev/md8 422M 422M 0B 100% /packages/mnt/jruntime-12.3R3.4 /dev/md9 7.9G 16K 7.2G 0% /tmp /dev/md10 7.9G 11M 7.2G 0% /mfs /dev/ad0s1e 393M 36K 362M 0% /config procfs 4.0K 4.0K 0B 100% /proc /dev/ad1s1f 18G 4.2G 12G 26% /var… and check the mounted partitions.
buraglio@rtr% mount /dev/ad0s1a on / (ufs, local, noatime) devfs on /dev (devfs, local, multilabel) /dev/md0 on /packages/mnt/jbase (cd9660, local, noatime, read-only, verified) /dev/md1 on /packages/mnt/jkernel64-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md2 on /packages/mnt/jpfe-X960-12.3R3.4 (cd9660, local, noatime, read-only) /dev/md3 on /packages/mnt/jdocs-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md4 on /packages/mnt/jroute-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md5 on /packages/mnt/jcrypto64-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md6 on /packages/mnt/jpfe-common-12.3R3.4 (cd9660, local, noatime, read-only) /dev/md7 on /packages/mnt/jplatform-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md8 on /packages/mnt/jruntime-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md9 on /tmp (ufs, asynchronous, local, noatime) /dev/md10 on /mfs (ufs, asynchronous, local, noatime) /dev/ad0s1e on /config (ufs, local, noatime) procfs on /proc (procfs, local, noatime) /dev/ad1s1f on /var (ufs, local, noatime)I ran a fsck to get some stats and see what the problem could be since it appears that there is no free space even though the router reports that it has it.
buraglio@rtr% fsck -y -f /dev/ad1s1f ** /dev/ad1s1f (NO WRITE) ** Last Mounted on /var ** Phase 1 - Check Blocks and Sizes ** Phase 2 - Check Pathnames ** Phase 3 - Check Connectivity ** Phase 4 - Check Reference Counts ** Phase 5 - Check Cyl groups FREE BLK COUNT(S) WRONG IN SUPERBLK SALVAGE? no 605 files, 2202492 used, 7040218 free (786 frags, 879929 blocks, 0.0% fragmentation)Playing around in the shell presented this error as well
/var: create/symlink failed, no inodes freeSo, it appears as if the /var partition is the issue. On my router /var is mounted as /dev/ad1s1f, so lets unmount this partition and try to fix it. In my experience Juniper will shy away from telling you to do anything in the shell, so do this at your own risk. Rebooting the router would also fix this issue, but I’m a form believer that rebooting networking equipment to fix issues is a lazy way to fix problems and will only serve to atrophy any troubleshooting skills you may have.
buraglio@rtr% umount -f /varNow run fsck again to repair the file system
buraglio@rtr% fsck -y -f /dev/ad1s1f ** /dev/ad1s1f ** Last Mounted on /var ** Phase 1 - Check Blocks and Sizes ** Phase 2 - Check Pathnames ** Phase 3 - Check Connectivity ** Phase 4 - Check Reference Counts ** Phase 5 - Check Cyl groups FREE BLK COUNT(S) WRONG IN SUPERBLK SALVAGE? yes 605 files, 2203376 used, 7039334 free (782 frags, 879819 blocks, 0.0% fragmentation) ***** FILE SYSTEM WAS MODIFIED *****Now that the problematic bits have been repaired, we re-mount the partition
buraglio@rtr% mount /dev/ad1s1f /var/Verify the mount
buraglio@rtr% mount /dev/ad0s1a on / (ufs, local, noatime) devfs on /dev (devfs, local, multilabel) /dev/md0 on /packages/mnt/jbase (cd9660, local, noatime, read-only, verified) /dev/md1 on /packages/mnt/jkernel64-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md2 on /packages/mnt/jpfe-X960-12.3R3.4 (cd9660, local, noatime, read-only) /dev/md3 on /packages/mnt/jdocs-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md4 on /packages/mnt/jroute-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md5 on /packages/mnt/jcrypto64-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md6 on /packages/mnt/jpfe-common-12.3R3.4 (cd9660, local, noatime, read-only) /dev/md7 on /packages/mnt/jplatform-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md8 on /packages/mnt/jruntime-12.3R3.4 (cd9660, local, noatime, read-only, verified) /dev/md9 on /tmp (ufs, asynchronous, local, noatime) /dev/md10 on /mfs (ufs, asynchronous, local, noatime) /dev/ad0s1e on /config (ufs, local, noatime) procfs on /proc (procfs, local, noatime) /dev/ad1s1f on /var (ufs, local, noatime)We should now be able to commit correctly.
buraglio@rtr% cli
{master}
buraglio@rtr>
{master}
buraglio@rtr> edit
Entering configuration mode
The configuration has been changed but not committed
{master}[edit]
buraglio@rtr# commit check
re0:
configuration check succeeds
re1:
configuration check succeeds
{master}[edit]
buraglio@rtr# commit
re0:
configuration check succeeds
re1:
commit complete
re0:
commit complete
{master}[edit]
buraglio@rtr#
And….you’re done. Hopefully this will help someone fight this problem, I only found a handful of other references to it that was useful but it didn’t address my exact scenario.