diff --git a/remotefilelog/remotefilelogserver.py b/remotefilelog/remotefilelogserver.py
--- a/remotefilelog/remotefilelogserver.py
+++ b/remotefilelog/remotefilelogserver.py
@@ -503,10 +503,17 @@
             for rev in ancestor.lazyancestors(fl.parentrevs,
                                               [fl.rev(n) for n in nodes],
                                               inclusive=True):
-                x, x, x, x, linkrev, p1, p2, node = fl.index[rev]
+                if util.safehasattr(fl, 'index'):
+                    # 4.7
+                    x, x, x, x, linkrev, p1, p2, node = fl.index[rev]
+                    p1node = fl.node(p1)
+                    p2node = fl.node(p2)
+                else:
+                    # 4.8
+                    linkrev = fl.linkrev(rev)
+                    node = fl.node(rev)
+                    p1node, p2node = fl.parents(node)
                 copyfrom = ''
-                p1node = fl.node(p1)
-                p2node = fl.node(p2)
                 linknode = repo.changelog.node(linkrev)
                 if p1node == nullid:
                     copydata = fl.renamed(node)
@@ -572,7 +579,15 @@
         while True:
             if cur in seen:
                 break
-            start, length, size, base, linkrev, p1, p2, node = fl.index[cur]
+            if util.safehasattr(fl, 'index'):
+                # 4.7
+                start, length, size, base, linkrev, p1, p2, node = fl.index[cur]
+            else:
+                # 4.8
+                base = fl.deltaparent(cur)
+                linkrev = fl.linkrev(cur)
+                node = fl.node(cur)
+                p1, p2 = fl.parentrevs(cur)
             if linkrev < stophint and cur != startrev:
                 break