The client log analysis. The lookup on '.snap/snapshot1' is successful from the dentry cache. The caps and the lease was valid and hence didn't ask mds. Please check the logs below.
158 2023-01-11T15:33:41.187+0530 7f1e3b7fe6c0 3 client.4134 ll_lookup 0x10000000000.snapdir snapshot1
159 2023-01-11T15:33:41.187+0530 7f1e3b7fe6c0 20 client.4134 may_lookup 0x10000000000.snapdir(faked_ino=0 nref=6 ll_ref=29 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:26:10.528194+0530 change_attr=1 caps=- 0x7f1e2ada7 b40); UserPerm(uid: 1000, gid: 1000)
160 2023-01-11T15:33:41.187+0530 7f1e3b7fe6c0 10 client.4134 _getattr mask As issued=0
...
...
193 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 10 client.4134 _getattr result=0
194 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 3 client.4134 may_lookup 0x7f1e2ada7b40 = 0
195 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 20 client.4134 _lookup have 0x10000000000.snapdir["snapshot1"] from mds.0 ttl 2023-03-02T08:27:56.510051+0530 seq 0
196 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 10 client.4134 _lookup 0x10000000000.snapdir(faked_ino=0 nref=7 ll_ref=29 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:26:10.528194+0530 change_attr=1 caps=- 0x7f1e2ada7b40 ) snapshot1 = 0x10000000000.2(faked_ino=0 nref=6 ll_ref=20 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:25:03.490655+0530 change_attr=1 caps=pAsLsXsFs COMPLETE parents=0x10000000000.snapdir["snapshot1"] 0x7f1e50008 100)
197 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 10 client.4134 fill_stat on 0x10000000000 snap/dev2 mode 040755 mtime 2023-01-11T15:24:05.398010+0530 ctime 2023-01-11T15:25:03.490655+0530
198 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 20 client.4134 _ll_get 0x7f1e50008100 0x10000000000 -> 21
199 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 3 client.4134 ll_lookup 0x10000000000.snapdir snapshot1 -> 0 (10000000000)
200 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 20 client.4134 put_inode on 0x10000000000.2(faked_ino=0 nref=6 ll_ref=21 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:25:03.490655+0530 change_attr=1 caps=pAsLsXsFs COMPLET E parents=0x10000000000.snapdir["snapshot1"] 0x7f1e50008100) n = 1
201 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 8 client.4134 _ll_forget 0x10000000000 1
202 2023-01-11T15:33:41.190+0530 7f1e3b7fe6c0 20 client.4134 _ll_put 0x7f1e2ada7b40 0x10000000000 1 -> 28
203 2023-01-11T15:33:41.190+0530 7f1e6b7fe6c0 20 client.4134 put_inode on 0x10000000000.head(faked_ino=0 nref=11 ll_ref=32 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:26:10.528194+0530 change_attr=1 caps=pAsLsXsFs(0=p AsLsXsFs) COMPLETE parents=0x1.head["dir1"] 0x7f1e50005660) n = 1
204 2023-01-11T15:33:41.190+0530 7f1e6b7fe6c0 20 client.4134 put_inode on 0x10000000000.snapdir(faked_ino=0 nref=7 ll_ref=28 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:26:10.528194+0530 change_attr=1 caps=- 0x7f1e2ad a7b40) n = 1
205 2023-01-11T15:33:41.190+0530 7f1e6b7fe6c0 20 client.4134 put_inode on 0x10000000000.head(faked_ino=0 nref=11 ll_ref=32 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:26:10.528194+0530 change_attr=1 caps=pAsLsXsFs(0=p AsLsXsFs) COMPLETE parents=0x1.head["dir1"] 0x7f1e50005660) n = 1
206 2023-01-11T15:33:41.190+0530 7f1e397fa6c0 20 client.4134 _ll_get 0x7f1e50008100 0x10000000000 -> 22
Similarly the lookup on 'snapshot1/file1-4GB' is also successful.
207 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 3 client.4134 ll_lookup 0x10000000000.2 file1-4GB
208 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 20 client.4134 may_lookup 0x10000000000.2(faked_ino=0 nref=6 ll_ref=22 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:25:03.490655+0530 change_attr=1 caps=pAsLsXsFs COMPLETE parents=0x10000000000.snapdir["snapshot1"] 0x7f1e50008100); UserPerm(uid: 1000, gid: 1000)
209 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 10 client.4134 _getattr mask As issued=1
210 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 3 client.4134 may_lookup 0x7f1e50008100 = 0
211 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 20 client.4134 _lookup have 0x10000000000.2["file1-4GB"] from mds.-1 ttl 0.000000 seq 0
212 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 10 client.4134 _lookup 0x10000000000.2(faked_ino=0 nref=6 ll_ref=22 cap_refs={} open={} mode=40755 size=0/0 nlink=1 btime=2023-01-11T15:23:58.011371+0530 mtime=2023-01-11T15:24:05.398010+0530 ctime=2023-01-11T15:25:03.490655+0530 change_attr=1 caps=pAsLsXsFs COMPLETE par ents=0x10000000000.snapdir["snapshot1"] 0x7f1e50008100) file1-4GB = 0x10000000001.2(faked_ino=0 nref=5 ll_ref=9 cap_refs={1024=0,2048=0} open={1=3} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388+0530 change_attr=3 2000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0)
213 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 10 client.4134 fill_stat on 0x10000000001 snap/dev2 mode 0100644 mtime 2023-01-11T15:24:37.324388+0530 ctime 2023-01-11T15:24:37.324388+0530
214 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 20 client.4134 _ll_get 0x7f1e500086d0 0x10000000001 -> 10
215 2023-01-11T15:33:41.191+0530 7f1e397fa6c0 3 client.4134 ll_lookup 0x10000000000.2 file1-4GB -> 0 (10000000001)
The open is also successful because it had caps.
220 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 3 client.4134 ll_open 0x10000000001.2 0
221 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 20 client.4134 may_open 0x10000000001.2(faked_ino=0 nref=5 ll_ref=11 cap_refs={1024=0,2048=0} open={1=3} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388+0530 change_attr=32 000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0); UserPerm(uid: 1000, gid: 1000)
222 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 10 client.4134 _getattr mask As issued=1
223 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 3 client.4134 may_open 0x7f1e500086d0 = 0
224 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 10 break_deleg: breaking delegs on 0x10000000001.2(faked_ino=0 nref=5 ll_ref=11 cap_refs={1024=0,2048=0} open={1=4} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388+0530 cha nge_attr=32000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0)
225 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 10 delegations_broken: delegations empty on 0x10000000001.2(faked_ino=0 nref=5 ll_ref=11 cap_refs={1024=0,2048=0} open={1=4} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388 +0530 change_attr=32000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0)
226 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 10 client.4134 check_caps on 0x10000000001.2(faked_ino=0 nref=5 ll_ref=11 cap_refs={1024=0,2048=0} open={1=4} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388+0530 change_at tr=32000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0) wanted pFscr used Fc issued pAsLsXsFscrl revoking - flags=1
227 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 20 client.4134 put_inode on 0x10000000001.2(faked_ino=0 nref=7 ll_ref=11 cap_refs={1024=0,2048=0} open={1=4} mode=100644 size=4194304000/0 nlink=1 btime=2023-01-11T15:24:05.398010+0530 mtime=2023-01-11T15:24:37.324388+0530 ctime=2023-01-11T15:24:37.324388+0530 change_att r=32000 caps=pAsLsXsFscrl objectset[0x10000000001 ts 0/0 objects 1000 dirty_or_tx 0] parents=0x10000000000.2["file1-4GB"] 0x7f1e500086d0) n = 1
228 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 10 client.4134 _create_fh 0x10000000001 mode 1
229 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 5 client.4134 open success, fh is 0x7f1e2ffd9820 combined IMMUTABLE SNAP caps pAsLsXsFscrl
230 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 20 client.4134 trim_cache size 4 max 16384
231 2023-01-11T15:33:41.192+0530 7f1e3bfff6c0 3 client.4134 ll_open 0x10000000001.2 0 = 0 (0x7f1e2ffd9820)