Can't install (create_ucs_failed)

is filesystem full?

How do I check that?

e.g.

[root@ve11a:Active:In Sync] config  df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg--db--sda-set.1.root
                      380M  212M  149M  59% /
/dev/mapper/vg--db--sda-set.1._config
                      3.0G   77M  2.8G   3% /config
/dev/mapper/vg--db--sda-set.1._usr
                      2.5G  1.8G  548M  77% /usr
/dev/mapper/vg--db--sda-set.1._var
                      3.0G  360M  2.5G  13% /var
/dev/mapper/vg--db--sda-dat.share.1
                       20G  3.8G   15G  21% /shared
/dev/mapper/vg--db--sda-dat.log.1
                      6.9G  155M  6.4G   3% /var/log
none                  2.0G  916K  2.0G   1% /dev/shm
none                  2.0G   28M  2.0G   2% /shared/rrd.1.2
none                  2.0G  5.4M  2.0G   1% /var/tmstat
none                  2.0G  1.5M  2.0G   1% /var/run
prompt                4.0M   28K  4.0M   1% /var/prompt
none                  2.0G     0  2.0G   0% /var/loipc

Looks ok.

[admin@DC1AAPM01:Active:Standalone] images  df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg--db--sda-set.2.root
                      380M  194M  167M  54% /
/dev/mapper/vg--db--sda-set.2._config
                      3.0G  140M  2.7G   5% /config
/dev/mapper/vg--db--sda-set.2._usr
                      2.2G  1.6G  466M  78% /usr
/dev/mapper/vg--db--sda-set.2._var
                      3.0G  333M  2.5G  12% /var
/dev/mapper/vg--db--sda-dat.share.1
                       30G  3.5G   25G  13% /shared
/dev/mapper/vg--db--sda-dat.log.1
                      6.9G  167M  6.4G   3% /var/log
none                  4.0G  916K  4.0G   1% /dev/shm
none                  4.0G   30M  3.9G   1% /shared/rrd.1.2
none                  4.0G   13M  3.9G   1% /var/tmstat
none                  4.0G  1.3M  4.0G   1% /var/run
prompt                4.0M   28K  4.0M   1% /var/prompt
none                  4.0G  8.0K  4.0G   1% /var/logd
none                  4.0G     0  4.0G   0% /var/loipc
/dev/mapper/vg--db--sda-app.ASWADB.set.2.mysqldb
                       12G 1001M   11G   9% /var/lib/mysql

Can you manually create ucs file? System \ Archive \ Create

If you had an replaced device, check this out https://support.f5.com/kb/en-us/solutions/public/9000/400/sol9420.html