I'll assume you are running Navisphere Manager 26 (with FLARE 23) and a newer version of Java.  While running a recent version of Java is not an issue necessarily in itself; however, you most likely answered "Yes" to a Java prompt asking:  "Block potentially unsafe components from being run? (recommended)"  This appears when you access certain displays within Navisphere Manager such as "System Properties".  Instinctively, people select "Yes", and I would agree it is recommended on webpages you aren't familiar with; however, that will unfortunately break functionality within the GUI as you had experienced.  I will mention though if you managed your array with Unisphere (via domain management), you wouldn't get this prompt.  You can confirm you had (accidentally) answered: "Yes" if you only see the tabs:  1) General 2) Cache  (NOTE: even though the Cache tab is displayed, several background Java scripts don't run)   On the other hand if you properly selected "No", then you'd see many more tabs:  1) General 2) Cache 3) Memory 4) Storage Access 5) Software   You have 2 solutions (*neither* requires disabling write cache or watermarks):  Solution #1 1) Close the GUI and clear both browser and java cache  2) When prompted, select "No" to the Java prompt  3) On the Cache tab modify in the following order: a) Change the High Watermark first  NOTE: This is important as the GUI checks that Low watermark is < High watermark.  If you were to try to change the Low watermark first, it would appear to not accept your input.  However, in this case the new lw (60%) > old hw (50%).  b) Change the Low Watermark, then click OK   Solution #2 Modify via CLI:  1) naviseccli -h setcache -l 60 -h 80   NOTE: only need to run on one SP as it is a "mirrored" option   2) naviseccli -h getcache   3) naviseccli -h getcache   NOTE: (optional) verify that both SP's report the updated values
Hi All, We set the cache low/high watermark levels to 30%/50%. I read some blogs, bloggers said EMC recommendation is 60%/80%. I would like to change the watermark levels as per EMC recommendation. what will happen when i change the watermark levels on production hours.  Storage Model: EMC Celerra NX-4  Backend: Clariion AX-4 5F8  Flare: 2.23.50.5.711 [IMAGE]
Cache watermark level change cause any downtime?